Automatic Transmission Overhaul - 4l60-e Chevrolet Corvette C5

APPLICATION

AUTOMATIC TRANSMISSION APPLICATIONS

IDENTIFICATION

Vehicle model is identified by 4th character (cars), or 5th character (trucks) of Vehicle Identification Number (VIN). VIN is stamped on metal pad on top of left end of instrument panel, near windshield. See MODEL IDENTIFICATION table.

The Hydra-Matic 4L60-E transmission can be identified by a letter code contained in identification number. Identification number is stamped on transmission case above oil pan rail on right rear side, or to rear of oil pan. (Scheme 1) Identification number contains information which must be used when ordering replacement parts. Transmission RPO code is M30.

MODEL IDENTIFICATION

Scheme 1

GEAR RATIOS

TRANSMISSION GEAR RATIOS

DESCRIPTION & OPERATION

The Hydra-Matic 4L60-E is a fully automatic transmission consisting of a 3-element hydraulic torque converter with a Torque Converter Clutch (TCC). The 4-speed transmission is equipped with 2 planetary gear sets, 5 multiple-disc clutches, one sprag clutch, one roller clutch and a 2-4 band. (Scheme 2)

A hydraulic system, pressurized by a variable capacity vane type oil pump, provides pressure required to operate friction elements and automatic controls. The 4L60-E contains electronic solenoids that control hydraulic operations. A Powertrain Control Module (PCM) or Vehicle Control Module (VCM) receives input signals from Vehicle Speed Sensor (VSS), Throttle Position (TP) sensor and Transmission Fluid Pressure (TFP) manual valve position switch which incorporates the fluid temperature sensor. These input signals help the PCM/VCM determine when to switch 2 shift solenoids, 3-2 downshift solenoid, and/or TCC solenoid on or off. PCM/VCM can control line pressure through pressure control solenoid (force motor).

Line pressure control system compensates for normal wear of transmission components during upshifts in order to maintain optimal shift quality during life of transmission. PCM/VCM uses "adaptive learning" to maintain acceptable upshift times by adjusting line pressure. PCM/VCM compares actual "acceptable" shift time to calibrated desired shift time and calculates difference. An "acceptable" shift is considered valid if no inconsistent vehicle operations (A/C compressor cycling or extreme throttle changes) occurred during upshift. Line pressure is either increased or decreased depending on duration of upshift time.

Scheme 2

LUBRICATION

Note. For additional information, see appropriate AUTOMATIC TRANSMISSION SERVICING article in TRANSMISSION SERVICING.

Note. The 4L60-E transmission used on Corvette is not equipped with a dipstick.

Transmission & Transfer Case

Manufacturer specifies Dexron(R) III ATF.

FLUID CAPACITIES

TRANSMISSION FLUID CAPACITIES (1)

TRANSFER CASE FLUID CAPACITIES (1)

ON-VEHICLE SERVICE

The following components may be serviced without transmission removal

1. Park/Neutral Position (PNP) Switch
2. Rear Oil Seal
3. 2-4 Servo Assembly
4. Valve Body & Solenoids
5. Vehicle Speed Sensor (VSS)

For service information on listed components, see appropriate component under REMOVAL & INSTALLATION .

OIL COOLER FLUSHING

1. If available, fill Line Flusher (J-35944) with solution, and install line flusher to transmission end of cooler line that feeds bottom fitting of transmission cooler. Connect discharge hose to top cooler line and attach drain hose to oil drain container. Follow line flusher manufacturer's instructions to flush oil cooler and cooler lines.
2. If line flusher is not available, flush cooler and cooler lines with a mixture of clean solvent and water. Flush cooler in both directions until all old fluid and debris are removed. If necessary, replace plugged or damaged cooler and/or lines.

TROUBLE SHOOTING

Note. For testing and diagnostic procedures of electronic components, see HYDRA-MATIC 4L60-E ELECTRONIC CONTROLS article.

PRELIMINARY INSPECTION

1. Before performing transmission trouble shooting, check fluid level, fluid condition and shift linkage adjustment. Check for stored DTCs. If any DTCs are present, diagnose and repair all computer-related DTCs. See HYDRA-MATIC 4L60-E ELECTRONIC CONTROLS article. If no DTCs are present, go to next step.
2. Perform road test. See «ROAD TEST»(/chevrolet/corvette/c5-1997-2004/remont/automatic-trans/#automatic-transmission-overhaul-4l60-e__road-test) under PERFORMANCE TESTS. During road test, record shift points. If shift point timing or shifting is incorrect, see HYDRA-MATIC 4L60-E ELECTRONIC CONTROLS article.
3. If shift(s) is too harsh or too soft, check hydraulic pressure. See «HYDRAULIC PRESSURE TESTS»(/chevrolet/corvette/c5-1997-2004/remont/automatic-trans/#automatic-transmission-overhaul-4l60-e__hydraulic-pressure-tests) under PERFORMANCE TESTS. For specific complaints, see appropriate condition(s) listed under «SYMPTOM DIAGNOSIS»(/chevrolet/corvette/c5-1997-2004/remont/automatic-trans/#automatic-transmission-overhaul-4l60-e) .

Fails To Shift

Possible faulty terminal crimp on transmission solenoid battery feed circuit between instrument panel fuse block and transmission solenoids. Check terminal crimp at bulkhead connector where circuit passes through firewall.

1st Gear Only, No Upshift

Sticking 1-2 shift valve in valve body. Spacer plate or gaskets damaged or not positioned properly. Case-to-valve body face damaged or not flat. 2-4 servo assembly restricted or blocked case passages. Nicks or burrs on servo pin or case pin bore. Missing or damaged piston or pin seals. 4th servo piston installed backward. 2-4 band worn or damaged, or band anchor pin not engaged. Stuck or damaged shift solenoids. Faulty shift solenoid circuit connections.

Slips In 1st Gear

Defective forward clutch assembly. Clutch plates worn. Piston porous or damaged. Piston seals missing or damaged. Input housing-to-forward clutch housing "O" ring seal missing or damaged. Damaged housing. Housing retainer and ball assembly damaged or not seating. Input shaft and housing assembly turbine shaft seals missing or damaged. Accumulator valve stuck in valve body.

Valve body face not flat, damaged lands, or interconnected passages. Spacer plate or gaskets incorrect, damaged or not positioned properly. Defective 1-2 accumulator piston assembly. Porosity in piston or cover and pin assembly. Damaged piston ring grooves. Piston seal missing or damaged. Cover gasket missing or damaged. Broken accumulator spring.

Incorrect oil pressure. Torque converter stator roller clutch not holding or 4th servo piston in backward. Damage to low roller clutch lugs or inner ramps. Rollers not free moving, inadequate spring tension or damage to inner splines. Oil passage plugged. Forward clutch accumulator piston seal missing or damaged. Piston out of its bore. Stuck abuse valve.

Slipping Or Rough 1-2 Shift

Defective valve body assembly. 1-2 shift valve train or accumulator valve stuck. Gaskets or spacer plate incorrect, damaged or not installed properly. Valve body face not flat.

Defective 2-4 servo assembly. Apply pin length incorrect. Servo seals or "O" ring seals missing or damaged. Restricted or missing oil passages. Case servo bore damaged. Defective 2nd accumulator. Porosity in 1-2 accumulator housing or piston. Piston seal or groove damaged. Nicks or burrs in 1-2 accumulator housing. Missing or restricted oil passages or 2-4 band worn or not positioned properly. Oil pump assembly or case surfaces not flat.

Slipping, Rough Or No 2-3 Shift

Defective valve body assembly. 2-3 shift valve train or accumulator valve stuck. Gaskets or spacer plate incorrect, damaged or not installed properly. Valve body face not flat.

Defective 2-4 servo assembly. Apply pin length incorrect. Servo seals or "O" ring seals missing or damaged. Restricted or missing oil passages. Case servo bore damaged. Defective 2nd accumulator. Porosity in 1-2 accumulator housing or piston. Piston seal or groove damaged. Nicks or burrs in 1-2 accumulator housing. Missing or restricted oil passages or 2-4 band worn or not positioned properly. Oil pump assembly or case faces not flat.

1st & 4th Or 2nd & 3rd Gear Only

Contaminated shift solenoids, damaged seals or faulty electrical connections.

3rd Gear Only

Faulty 2-3 shift solenoid and 3-2 control solenoid circuits, damaged seals or faulty electrical connections.

No 2nd, 4th & Reverse Gears

Transmission may have been assembled with an older style sun gear reaction shell. Earlier production shells were manufactured with reduced tolerances (thinner material) around area attaching splines to the shell, resulting in fatigue failure of the shell. Old and new style shells can be identified by the alpha-numeric identification number stamped inside shell. Identification number beginning with "A" or "B" is old style. Identification beginning with "T" or "W" is new style. General Motors part number (8683439) is the same for old and new styles. Updated part must be verified with alpha-numeric identification number.

3-2 Flare Or Tie Up

Contaminated 3-2 control solenoid, damaged seals or faulty electrical connections.

Slipping, Rough Or No 3-4 Shift

Oil pump assembly faces not flat or pump cover retainer and ball assembly omitted or damaged. Valve body assembly 2-3 shift train, accumulator valve, 1-2 shift valve or 3-2 control valve stuck. Manual valve link bent or damaged. Spacer plate or gaskets incorrect, damaged or not positioned properly. Defective 2-4 servo assembly.

Incorrect band apply pin. Servo seals missing or damaged. Porosity in pistons, cover or case. Plugged or missing orifice cup plug. Case 3rd accumulator retainer and ball assembly leaking. Porosity in 3-4 accumulator piston or bore. 3-4 accumulator piston seal or seal grooves damaged. Restricted oil passage. Defective input housing assembly. Forward or 3-4 clutch plates worn, or excessive plate travel.

Forward or 3-4 piston seals damaged. Porosity in 3-4 clutch housing or piston. 3-4 piston check ball stuck, damaged or not sealing. Restricted apply passages. Forward clutch piston retainer and ball assembly not seating. 2-4 band worn or not positioned properly. Sealing balls loose or missing.

No Reverse Or Slips In Reverse

Defective input housing assembly. 3-4 apply ring stuck in applied position. Forward clutch not releasing. Turbine shaft seals missing or damaged. Manual valve link disconnected.

Defective valve body assembly. 2-3 shift valve stuck. Manual linkage out of adjustment. Spacer plate and gaskets incorrect, damaged or not positioned properly. Defective reverse input clutch assembly. Clutch plate worn. Housing and drum assembly cracked at weld. Clutch plate or return spring assembly retaining ring out of groove. Piston deformed or dished.

Seals damaged or missing. Retainer and ball assembly not sealing. Restricted apply passage. Defective low-reverse clutch. Clutch plates worn or retaining ring not positioned properly. Porosity in piston. Seals damaged. Return spring assembly retaining ring not positioned properly. Case porosity. Case cover plate not tightened properly or gasket missing or damaged.

No Part-Throttle Or Delayed Downshifts

Defective 2-4 servo assembly. Servo cover retaining ring missing or not assembled properly. 4th apply piston damaged or not assembled properly. Inner housing damaged or not assembled properly. Defective valve body assembly. 3-2 control valve stuck. 4-3 sequence valve body channel blocked. No. 5 check ball missing.

Harsh Garage Shifts

Missing valve body check ball or orifice cup plug.

No Overrun Braking In Manual 3-2-1

Defective valve body assembly. 4-3 sequence valve or throttle valve stuck. No. 3 check ball not positioned properly. Spacer plate and gaskets incorrect, damaged or not positioned properly. Defective input clutch assembly. Turbine shaft oil passages plugged or not drilled. Turbine shaft seal rings damaged. Turbine shaft sealing balls loose or missing. Porosity in forward or overrun clutch piston. Overrun piston seals damaged or cut. Overrun piston check ball not sealing.

Drives (Creeps) In Neutral

Forward clutch not releasing. Manual valve link disconnected. Converter clutch apply valve stuck in oil pump. Face of transmission case not flat or internal leakage in case.

Starts In 2nd In "D"

Forward sprag clutch assembly installed backward.

No Parking Gear

Parking linkage binding, loose, missing or not positioned properly.

Oil Pressure High Or Low

Oil pressure regulator valve stuck or valve spring damaged. Rotor guide omitted or not assembled properly. Rotor cracked or reverse boost valve or sleeve stuck, damaged or not assembled properly. Orifice hole in pressure regulator valve plugged. Sticking slide or excessive rotor clearance. Pressure relief ball not seated or damaged. Pump cover or body has porosity. Incorrect pump cover or pump face not flat. Excessive rotor clearance.

Intake pipe restricted by casting flash. Cracks in filter body or intake pipe. "O" ring seal missing, cut or damaged. Incorrect lubricant used during rebuild procedure.

Manual valve scored or damaged. Spacer plate or gaskets incorrect, damaged or not assembled properly. Stuck 2-3 shift valve, damaged pressure control solenoid or damaged pressure switch assembly. Missing check balls or incorrect assembly. Case-to-valve body face not flat.

Harsh Shifts

Faulty PCM/VCM input signals from TP sensor, pressure switch assembly, fluid temperature sensor, VSS and engine coolant temperature sensor. Damaged pressure control solenoid pins or seals, or dirt in oil circuits.

High Or Low Shift Points

Stuck pressure regulator valve or pump slide sticking. Spacer plate or gaskets damaged, incorrect or not assembled properly.

Valve body pad porous or damaged. 2-4 accumulator has porosity. Servo piston seals damaged. Apply pin damaged or improper length. 2-4 band burned or anchor pin not engaged. Throttle Position (TP) sensor, VSS and/or 4WD low switch (if equipped) disconnected or damaged.

No Converter Clutch Apply

Transmission not supplied 12 volts. Outside electrical connector damaged. Inside electrical connector wiring harness or solenoid damaged. Solenoid wire pinched. Solenoid not grounded. Pressure switches incorrect or damaged. Temperature sensor damaged. Damaged engine speed sensor or pressure switch assembly. Converter internal damage.

Converter clutch valve stuck or assembled backward, or retaining ring not positioned properly. Pump-to-case gasket not positioned properly. Orifice cup plug restricted or damaged. Solenoid "O" ring seal cut or damaged. Pump-to-body cover high or uneven bolt torque. Turbine shaft "O" ring seal cut or damaged. Turbine shaft retainer and ball assembly restricted or damaged. TCC shift valve or apply valve stuck. Solenoid "O" ring leaking. Solenoid screen is blocked.

Converter Shudder

Torque converter has internal damage. Converter clutch valve stuck. Restricted oil passages. Crack in filter body. Restriction in filter neck. "O" ring seal cut or damaged. Turbine shaft "O" ring cut or damaged. Turbine shaft retainer and ball assembly restricted or damaged. Low oil pressure. Engine not tuned properly.

No Converter Clutch Release

Solenoid external ground. Converter internal damage. Converter clutch valve stuck. Converter clutch apply valve stuck in apply position. PCM/VCM external ground faulty.

Converter Clutch Applies When Cold

Faulty engine coolant temperature sensor. Check for trouble codes.

Ratcheting Noise

Parking pawl return spring weak, damaged or not assembled properly.

Oil Leaking Out Vent

Chamber in pump body rotor pocket too large. Fluid level overfilled. Cross leak in pump body and cover.

Vibration In Reverse & Whining Noise In Park

Broken oil pump vane rings.

Front Oil Leak

Torque converter welded seam leaking. Damaged torque converter hub. Damaged front seal.

Pump Bushing Spins Out, "Walks" Into Seal Or Seizes To Converter Hub

Transmission and engine center lines do not match. Excessive crankshaft runout. Bent flexplate (drive plate). Excessive converter hub runout. Pump bushing I.D. not centered in pump. Bushing too loose in pump. Not enough hub-to-bushing clearance.

Falls Out Of 4th Gear During Coasting

Low line pressure at idle (weak pressure regulator spring).

Binds Up On 3-4 Shift (Feels Like Brake Drag)

Forward pressure plate installed incorrectly. Too many plates in overrun clutch. Incorrect top steel plate installed in overrun clutch.

No Forward Or Reverse Gears (Line Pressure Reading Okay)

Mismatched converter input shaft or broken turbine hub.

Binds Up In Reverse

Stator sleeve rotated out of position. Stuck 2-3 shift valve. Servo pin jammed in case. Stuck 3-4 relay or 4-3 sequence valve.

No Drive In "D" Range

Torque converter stator roller clutch not holding.

No Drive In "OD" Range

Faulty output sprag. Teeth "hammered" out of forward friction plates.

CLUTCH & BAND APPLICATIONS

CLUTCH & BAND APPLICATIONS

PERFORMANCE TESTS

Note. Shift speed tables reference throttle angle percent and output shaft speed. Both conditions are monitored using scan tool. Shift speed tables apply when transmission is in "D" (Overdrive) position while vehicle is driven in 4 forward gears. Ensure vehicle speed listed in road test procedures corresponds with output shaft speed indicated in shift speed tables. Upshifts and downshifts should occur at specified output shaft speed noted in shift speed tables. Warm up information in shift speed tables applies to open loop operation. Before road testing vehicle, engine and transmission must be at operating temperature. Torque converter clutch will not engage if engine coolant has not reached operating temperature.

ROAD TEST

If transmission shift speeds are not as specified during road test, check for DTCs. See HYDRA-MATIC 4L60-E ELECTRONIC CONTROLS article. If slippage occurs, determine which components are applied in each gear to aid in diagnosis. See CLUTCH & BAND APPLICATIONS under TROUBLE SHOOTING. Perform hydraulic pressure test to check transmission internal components. See HYDRAULIC PRESSURE TESTS .

Note. Perform the following tests in the sequence given. Ensure engine is operating properly, and transmission fluid level and tire pressure are correct.

Electrical Function Check

1. Connect scan tool. Ensure gearshift lever is in Park and parking brake is set. Start engine. Using scan tool, ensure the following data can be displayed and is functioning properly: Engine Speed Transmission Output Speed Vehicle Speed TFP Manual Valve Position Switch Transmission Range Commanded Gear (Current Gear) PC Solenoid Reference Current PC Solenoid Actual Current PC Solenoid Duty Cycle Brake Switch Engine Coolant Temperature Transmission Fluid Temperature Throttle Angle Ignition Voltage 1-2 Shift Solenoid 2-3 Shift Solenoid TCC Solenoid Duty Cycle TCC Slip Speed If all data is displayed and appears accurate, go to next step. If any data is in question, diagnose and repair as necessary. See HYDRA-MATIC 4L60-E ELECTRONIC CONTROLS article or appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE.
2. Using scan tool, monitor brake switch signal while depressing and releasing brake pedal. Ensure scan tool displays CLOSED with brake pedal released and OPEN with brake pedal depressed.
3. Apply brake pedal and set parking brake. Move gearshift lever from Park to Reverse, Reverse to Neutral, and then from Neutral to Drive. Pause 2-3 seconds in each range. Ensure engagements are immediate and not harsh.
4. Using scan tool, monitor transmission range. Move gearshift lever through all ranges. Pause in each range for 2-3 seconds and return gearshift lever to Park. Ensure all gearshift lever positions match scan tool display.
5. Using scan tool, monitor throttle angle while increasing and decreasing engine speed with accelerator pedal. Ensure actual engine speed matches engine speed displayed on scan tool.
6. Record test results in question for reference and continue with road test.

Upshift Control & Torque Converter Clutch Apply

Note. To include normal driving ranges in the following test, check shift speeds at 12, 25 and 50 percent throttle angles.

1. Using scan tool, monitor the following parameters: Throttle Angle Vehicle Speed Engine Speed Output Shaft Speed Commanded Gear Slip Speed Solenoid States Place gearshift lever in Overdrive. Accelerate vehicle to chosen throttle angle (12, 25 or 50 percent) and hold steady. As transmission upshifts, note vehicle speed as shift occurs for each gear change. Compare shift speeds with specification. (Scheme 3)- (Scheme 7). Check for harsh, soft or delayed shifts. Note any noise or vibration. Repeat procedure for each throttle angle.
2. Check for TCC apply in 3rd and 4th gear. Note TCC apply point. Typical TCC apply speed is 30-32 MPH in 3rd gear, and 40-45 MPH in 4th gear. A noticeable drop in engine RPM should be observed, and slip speed should decrease to less than 100 RPM. Ensure TCC apply speed is within specification and TCC disengages with light application of brake pedal. If TCC apply is not detected, check for DTCs. See HYDRA-MATIC 4L60-E ELECTRONIC CONTROLS article. Check TCC operation. See «TORQUE CONVERTER DIAGNOSIS»(/chevrolet/corvette/c5-1997-2004/remont/automatic-trans/#automatic-transmission-overhaul-4l60-e__torque-converter-diagnosis).

Scheme 3

Scheme 4

Scheme 5

Scheme 6

Scheme 7

Part Throttle Detent Downshift

Place gearshift lever in Overdrive. Accelerate vehicle to 40-55 MPH in 4th gear. Quickly increase throttle angle greater than 50 percent. Ensure TCC releases, and transmission immediately downshifts to 3rd gear.

Full Throttle Detent Downshift

Place gearshift lever in Overdrive. Accelerate vehicle to 40-55 MPH in 4th gear. Quickly increase throttle angle to 100 percent. Ensure TCC releases, and transmission immediately downshifts to 2nd gear.

Manual Downshifts

1. Place gearshift lever in Overdrive. Accelerate vehicle to 40-55 MPH in 4th gear. Release throttle while moving gearshift lever to 3rd gear. Ensure TCC releases, transmission immediately downshifts to 3rd gear, and engine slows vehicle (engine braking).
2. Place gearshift lever in Overdrive. Accelerate vehicle to 40-45 MPH. Release throttle while moving gearshift lever to 2nd gear. Ensure TCC releases, transmission immediately downshifts to 2nd gear, and engine slows vehicle (engine braking).
3. Place gearshift lever in Overdrive. Accelerate vehicle to 30 MPH. Release throttle while moving gearshift lever to 1st gear. Ensure TCC releases, transmission immediately downshifts to 1st gear, and engine slows vehicle (engine braking).

Coasting Downshifts

Place gearshift lever in Overdrive. Accelerate vehicle to 4th gear and ensure TCC is applied. Release throttle and lightly apply brake pedal. Ensure TCC releases, and downshifts occur at specified vehicle speeds. (Scheme 3)- (Scheme 7).

Manual Gear Range Selection

Note. Shift solenoids control upshifts in manual gear ranges. Perform the following tests with 15 percent throttle angle.

1. With vehicle stopped, place gearshift lever in Reverse. Slowly accelerate vehicle. Ensure there is no noticeable slip, noise or vibration.
2. With vehicle stopped, place gearshift lever in manual 1st gear. Accelerate vehicle to 20 MPH. Ensure no upshifts occur, TCC does not apply and there is no noticeable slip, noise or vibration.
3. With vehicle stopped, place gearshift lever in manual 2nd gear. Accelerate vehicle to 35 MPH. Ensure 1-2 upshift occurs, and there is no noticeable slip, noise or vibration.
4. With vehicle stopped, place gearshift lever in manual 3rd gear. Accelerate vehicle to 40 MPH. Ensure 1-2 and 2-3 upshifts occur, and there is no noticeable slip, noise or vibration.

TORQUE CONVERTER DIAGNOSIS

Note. Torque converter is a sealed unit and can not be disassembled. Manufacturer does not recommend testing torque converter stall speed.

Stator Check

1. Torque converter stator roller clutch may fail and can either remain locked up at all times or freewheel in both directions. If stator is freewheeling at all times, vehicle tends to have poor acceleration from a standstill. Vehicle may operate normally at speeds greater than 30-35 MPH.
2. If poor acceleration is noted, ensure exhaust system is not blocked, engine timing is correct and transmission is in 1st gear when starting from a standstill. If stator is locked up at all times, performance from a standstill will appear normal. Engine RPM and acceleration is limited at high speeds. Engine may overheat from this condition. A visual inspection of torque converter may reveal converter is Blue in color indicating an overheat condition.

Noise Test

1. Torque converter whine is usually noticed when vehicle is stopped and transmission is in Reverse or Drive. Whine will increase when engine RPM is increased and will stop when vehicle is moving or when torque converter clutch is applied. Ensure whine originates from torque converter.
2. Start engine, and allow it to reach normal operating temperature. Apply parking and service brakes. Place transmission in Drive. Depress accelerator pedal to increase engine speed to about 1200 RPM for less than 6 seconds. DO NOT depress accelerator for more than 6 seconds or transmission damage may occur. Torque converter noise will increase under this load.

Note. Torque converter whine should not be confused with pump whine, which is usually noticeable in Park, Neutral and all other gear ranges. Pump whine will vary with pressure.

HYDRAULIC PRESSURE TESTS

1. Before performing hydraulic pressure test, check fluid level and condition. Check manual control linkages for correct adjustment, and ensure engine is properly tuned.
2. Connect scan tool to Data Link Connector (DLC). Apply parking brake and start engine. Check for stored Diagnostic Trouble Codes (DTC). If DTCs are present, diagnose as necessary. See HYDRA-MATIC 4L60-E ELECTRONIC CONTROLS article. Turn engine off. Connect oil pressure gauge to line pressure test port. (Scheme 8)
3. Start engine and warm to normal operating temperature. With vehicle in Reverse, line pressure should be 64-324 psi (441-2234 kPa). With vehicle in Park, Neutral or Drive, line pressure should be 55-189 psi (379-1303 kPa).
4. Shift transaxle into Park. Access Pressure Control Solenoid (PCS) test on scan tool. Increase DESIRED PCS in.1 amp increments and read corresponding line pressure on oil pressure gauge. Allow pressure to stabilize for 5 seconds after each current change. Compare readings to specifications. See «LINE PRESSURE SPECIFICATIONS»(/chevrolet/corvette/c5-1997-2004/remont/automatic-trans/#automatic-transmission-overhaul-4l60-e) table. If pressure readings are not as specified, and no DTCs are present, an internal malfunction exists. See «TROUBLE SHOOTING»(/chevrolet/corvette/c5-1997-2004/remont/automatic-trans/#automatic-transmission-overhaul-4l60-e__trouble-shooting).

Note. Scan tool is only able to control pressure control solenoid in Park and Neutral with vehicle stopped. This protects clutches from extremely high or low pressures in Reverse and Drive.

LINE PRESSURE SPECIFICATIONS

Scheme 8

Inspection

A visual inspection of torque converter may reveal converter is Blue from overheating. If torque converter has been removed from vehicle, stator roller clutch can be checked by inserting a finger into splined inner race of roller clutch and attempting to rotate race in both directions. Inner race should rotate freely clockwise, but should not rotate or should be difficult to rotate counterclockwise.

Torque converter must be replaced for any of the following reasons

1. Damage To Pump Assembly
2. Metal Particles Present In Oil
3. Leaks In Hub Weld Area
4. Hub Scored Or Damaged
5. Stator Failure
6. Torque Converter Imbalance
7. Engine Coolant Contamination
8. Excessive End Play

Torque Converter End Play Check

1. Inspect torque converter for hub scoring, cracks or weld area cracks before checking end play. Install End Play Checking Tool (J-35138) on torque converter. (Scheme 9)
2. Note end play of torque converter. End play must be within specification. See «TORQUE CONVERTER END PLAY SPECIFICATIONS»(/chevrolet/corvette/c5-1997-2004/remont/automatic-trans/#automatic-transmission-overhaul-4l60-e) table. Replace torque converter if end play is not within specification or damage to hub area exists.

TORQUE CONVERTER END PLAY SPECIFICATIONS

Scheme 9

REMOVAL & INSTALLATION

Note. Transmission Adaptive Pressure (TAP) values may require to be reset if one of the following repairs has been performed: Transmission overhaul or replacement. Repair or replacement of an apply or release component (band, clutch, piston and/or servo). Repair or replacement of a component or assembly which directly affects transmission line pressure. To reset TAP values, see CLEARING & RESETTING TAP VALUES in HYDRA-MATIC 4L60-E ELECTRONIC CONTROLS article.

PARK/NEUTRAL POSITION SWITCH

Note. If wire harness and connectors are melted to Park/Neutral Position (PNP) switch body, upgraded replacement parts are available; PNP Switch (12450016), Large Connector (15305887) and Small Connector (15305925).

Removal

Apply parking brake. Shift transmission to "N" position. Remove control lever from manual shaft. Disconnect wiring harness connector at vehicle harness. Do not disconnect harness at switch. Remove PNP switch from manual shaft.

Scheme 10

1. Ensure manual shaft is free of burrs. Repair as necessary. Install PNP switch on manual shaft. Align switch hub flats with manual shaft flats. Install 2 bolts securing switch to case finger tight.
2. Using PNP Switch Alignment Tool (J41364-A), align 2 lower slots on PNP switch with upper slot on PNP switch by rotating switch body. (Scheme 10) Tighten PNP switch mounting bolts to 18 ft. lbs. (25 N.m).
3. Install transmission shift lever bracket and shift cable. Tighten transmission shift lever nut to 18 ft. lbs. (25 N.m). Check PNP switch operation. Ensure engine starts with transmission in Park and Neutral only.

Mark drive shaft for reassembly reference. Remove drive shaft. Pry oil seal from extension housing. Coat outside edge of NEW oil seal with non-hardening sealer. Using Seal Installer (J-21426), install oil seal. To complete installation, install drive shaft. Check fluid level.

VALVE BODY

1. Remove transmission oil pan. Remove oil filter and "O" ring. Ensure "O" ring is removed from transmission case. Remove electrical connectors from switches and solenoids, and mark for reassembly reference. Remove TCC PWM solenoid retainer clip. Remove solenoid. (Scheme 11)
2. Remove TCC solenoid bolts. Remove valve body bolts securing wiring harness. Remove TCC solenoid and allow wiring harness to hang over side of case. Remove transmission fluid pressure manual valve position switch. Remove detent spring bolt. Remove detent spring. Remove remaining valve body bolts. Note length and location of bolts for installation reference. (Scheme 12)
3. Note direction of manual valve link. Remove manual valve link from manual valve at valve body. (Scheme 13) Remove valve body. Note location of check balls. (Scheme 14)and (Scheme 15).

Installation

1. Coat check balls with petroleum jelly. Install check balls in proper locations on separator plate. (Scheme 14)and (Scheme 15). Install manual valve link. Ensure manual valve link is properly seated in manual valve. (Scheme 13) Improper positioning will result in erratic shift points, high oil pressure, or may prevent vehicle operation in "D" range.
2. Install valve body and retaining bolts. Tighten all bolts to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/corvette/c5-1997-2004/remont/automatic-trans/#automatic-transmission-overhaul-4l60-e__torque-specifications). Lubricate oil filter "O" ring with ATF before installation. To complete installation, reverse removal procedure. Fill transmission with appropriate fluid to proper level. See «LUBRICATION»(/chevrolet/corvette/c5-1997-2004/remont/automatic-trans/#automatic-transmission-overhaul-4l60-e__lubrication).

Scheme 11

Scheme 12

Scheme 13

Scheme 14

Scheme 15

Note. See appropriate AUTOMATIC TRANSMISSION REMOVAL article in TRANSMISSION SERVICING.

1. Raise and support vehicle. Disconnect harness connector at Vehicle Speed sensor (VSS). Remove bolt securing VSS to extension housing. Using VSS removal tool (J38417), remove VSS. Catch fluid leakage with suitable container.
2. To install VSS, reverse removal procedure using NEW "O" ring. Tighten bolt to 97 INCH lbs. (11 N.m). Check fluid level. See «LUBRICATION»(/chevrolet/corvette/c5-1997-2004/remont/automatic-trans/#automatic-transmission-overhaul-4l60-e__lubrication) .

Install Piston Compressor (J-29714) on oil pan. Compress servo cover, and remove retaining ring. (Scheme 16) Remove servo cover and "O" ring. Remove 2-4 servo assembly. To install, reverse removal procedure. For servo pin length check, see 2-4 SERVO ASSEMBLY under TRANSMISSION DISASSEMBLY.

Scheme 16

CONVERTER HOUSING

Mount transmission on bench using Holding Fixture (J-8763-02). Remove torque converter. Using 50 mm Torx Plus Bit (J-41510), remove converter housing bolts, and remove converter housing.

2-4 SERVO ASSEMBLY

Install Servo Cover Compressor (J-29714-A) on oil pan. (Scheme 16) Compress servo cover. Remove retaining ring, servo cover and "O" ring. Remove 2-4 servo assembly.

EXTENSION HOUSING

Remove Vehicle Speed Sensor (VSS) retaining bolt. Remove speed sensor assembly and "O" ring. (Scheme 20) Remove extension housing and seal. Remove output shaft sleeve and "O" ring (if equipped). Remove speed sensor rotor from output shaft (if necessary). Install Gear Puller (J-21427-01) and Adapter (J-8433) on rotor. Pull rotor from output shaft. Install Output Shaft Support Fixture (J-29837-A) on output shaft. (Scheme 17)

Scheme 17

VALVE BODY, 1-2 & 3-4 ACCUMULATORS

1. Remove transmission oil pan. Remove oil filter and "O" ring. Ensure "O" ring is removed from transmission case. Remove electrical connectors from switches and solenoids, and mark for reassembly reference. Remove TCC PWM solenoid retainer clip. Remove solenoid. (Scheme 11)
2. Remove TCC solenoid bolts. Remove valve body bolts securing wiring harness. Remove TCC solenoid and allow wiring harness to hang over side of case. Remove transmission fluid pressure manual valve position switch. Remove detent spring bolt. Remove detent spring. Remove remaining valve body bolts. Note length and location of bolts for installation reference. (Scheme 12)
3. Note direction of manual valve link. Remove manual valve link from manual valve at valve body. (Scheme 13) Remove valve body. Note location of check balls on valve body. (Scheme 14)and (Scheme 15).
4. Carefully remove accumulator cover retaining bolts, 1-2 accumulator cover and pin assembly. (Scheme 21) Remove 1-2 accumulator piston, seal and spring. Remove spacer plate beside 1-2 accumulator. Note check ball and filter locations. (Scheme 15) Remove spacer plates. Remove spring, 3-4 accumulator piston and pin.

OIL PUMP, INPUT CLUTCH & REVERSE CLUTCH

1. Ensure TCC solenoid assembly and oil filter are removed before oil pump removal. Remove turbine shaft "O" ring. Remove oil pump retaining bolts. Using Oil Pump Remover (J-37789-A) and Adapter (J-39119), pull oil pump assembly free from case. (Scheme 18)
2. Remove oil pump, seal and gasket. Remove reverse input clutch-to-pump thrust washer from pump. Lift out input housing, shaft assembly, reverse input clutch housing and drum assembly.

Scheme 18

2-4 BAND, INPUT GEAR SET & REACTION GEAR SET

1. Remove band anchor pin from case. (Scheme 19) Remove 2-4 band assembly from case. Remove input sun gear. (Scheme 22)
2. Remove input carrier-to-output shaft retainer ring. Remove input carrier (planetary). Remove input carrier thrust bearing from reaction carrier shaft.
3. Remove input internal gear and reaction carrier shaft. Remove reaction sun shell and thrust washer. Remove sun shell-to-clutch race thrust washer. Remove reaction sun gear, low-reverse roller clutch race and roller clutch.

Scheme 19

Scheme 20

Scheme 21

Scheme 22

LOW-REVERSE CLUTCH

Note. Parking pawl may require removal to access low-reverse clutch.

1. Remove low-reverse support-to-case retaining snap ring. Remove output shaft support fixture. (Scheme 17) Push up on output shaft to loosen low-reverse clutch support. Remove support retainer spring from low-reverse support. Remove low-reverse support assembly and reaction carrier assembly (planetary). (Scheme 22)
2. Remove low-reverse clutch plates. Note locations of components. Remove internal reaction gear and thrust bearing. Remove internal reaction gear support-to-case thrust bearing. Remove output shaft.
3. Remove parking lock bracket retaining bolts. Remove lock bracket. Using screw extractor, remove shaft plug. Remove parking pawl shaft, parking pawl and return spring if necessary. (Scheme 24)
4. Using Clutch Spring Compressor (J-23327), compress low reverse clutch spring retainer. Remove spring retaining ring and low-reverse spring assembly. Remove low-reverse clutch piston by applying air pressure in case apply passage. (Scheme 23)

Scheme 23

INNER MANUAL SHAFT LINKAGE

Remove manual shaft nut. Remove manual shaft and retainer. Remove parking lock actuator assembly and inner detent lever. Remove manual shaft seal from transmission case. (Scheme 24)

Scheme 24

3RD ACCUMULATOR RETAINER & BALL ASSEMBLY

1. Check 3rd accumulator retainer and ball assembly before removing it. DO NOT remove check valve unless it is leaking. Install servo assembly in bore. Install servo cover and retaining ring. (Scheme 16) Pour clean solvent in bore. Inspect for leaks in transmission case. Replace check valve assembly if it leaks. (Scheme 25) Remove servo assembly.
2. For check valve removal, install No. 4 screw extractor in check valve assembly. Remove check valve. Ensure bore is free of burrs. Installation tool must be made to ensure proper installation depth is obtained. Using a 3/8" O.D. rod, scribe indicator mark at 1.653" (41.98 mm) from end of rod. Install check valve until scribe mark on rod is flush with case. (Scheme 25) Ensure slot in retainer is completely open. Observe 3rd accumulator retainer and ball assembly in 2-4 band servo bore.

Scheme 25

Disassembly

1. Remove reverse input clutch drum-to-oil pump thrust washer, pump-to-case gasket and pump-to-case oil seal ring from pump assembly. Remove pump cover retaining bolts. Separate pump cover from pump body.
2. Using needle-nose pliers, compress pump slide spring. Remove from pump by pulling straight out. Remove pump vane rings, pump vanes, pump rotor and rotor guide from pump pocket.
3. Remove slide from pump pocket. Remove slide seal and seal support from pump slide. (Scheme 26) Remove pivot pin and pivot pin spring. Remove seal ring and "O" ring from pump slide. Remove seal retainer and seal from pump body.
4. Check condition of pump bushing. If bushing is in good condition, do not remove it. Push inward on converter clutch valve stop to compress spring. Remove snap ring. Remove valve stop, converter clutch apply valve and springs.
5. Using small punch, remove pressure relief spring retaining rivet. Remove relief spring and check ball. Remove oil screen and "O" ring from pump cover. Remove reverse boost valve sleeve. Remove reverse boost valve, pressure regulator valve spring and pressure regulator valve.

Scheme 26

1. Inspect all valves, springs, sleeves and bushings for chips, burrs, distortion and free movement in bores. Check pressure relief check ball and spring for damage and distortion. Low line pressure will result if check ball and spring are damaged.
2. Inspect pump cover screen and "O" ring for wear and damage. Clean pump body and cover. Check all bores for obstructions. Inspect mating sides of cover and body for scoring, flatness and damage between channels. Check channels for dirt and damaged passages. Inspect stator shaft and pump body bushings for damage.
3. Inspect rotor and slide for scoring, cracks and damage. Check rotor guide and pump vane rings for excessive wear and damage. Inspect all seals for damage.
4. Measure pump rotor and slide thickness for surface wear. Rotor and slide measurements must fall into same thickness range. See «OIL PUMP COMPONENT THICKNESS»(/chevrolet/corvette/c5-1997-2004/remont/automatic-trans/#automatic-transmission-overhaul-4l60-e) table. If rotor and slide measurements do not fall into same thickness range, or are outside of all ranges, oil pump must be replaced as an assembly.

OIL PUMP COMPONENT THICKNESS

Reassembly

1. Install "O" ring and seal ring in groove on back side of pump slide. Retain seal ring using petroleum jelly. Install pivot pin and spring in pump body. Install pump slide. Notch in pump slide must align with pivot pin hole and with flat oil seal ring facing downward in pump pocket. Install slide seal and support.
2. Install pump vane ring into pump pocket. Coat rotor guide with petroleum jelly. Install rotor guide on rotor. Install rotor and guide into pump pocket with guide toward pump pocket. Install vanes in rotor. Install vane guide ring. Compress pump slide spring and install into pump pocket. All parts must be even with pump body surface. Install "O" ring on pump screen, and install screen in pump cover with "O" ring end out.
3. Install oil seal in pump body. Install seal retainer. Install pressure relief check ball and spring in pump cover. Install retaining rivet. Install converter clutch valve springs and converter clutch valve. Install valve stop and snap ring. Install pressure regulator valve and spring in pump cover. (Scheme 26)
4. Coat reverse boost valve with petroleum jelly. Install reverse boost valve in boost valve sleeve with small end first. Install reverse boost valve sleeve in pump cover.
5. Install pump cover on pump body. Install retaining bolts finger tight. Align pump body and cover using Alignment Strap (J-21368). (Scheme 27) Place bolt through pump-to-case bolt hole. Tighten retaining bolts to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/corvette/c5-1997-2004/remont/automatic-trans/#automatic-transmission-overhaul-4l60-e__torque-specifications). Remove alignment strap. Position pump-to-case gasket on pump, and retain with petroleum jelly.
6. Install oil seal rings on stator hub. Place Stator Shaft Seal Installer (J39855-1) over oil pump stator hub (stator support). (Scheme 28) Set height of installer tool to just above seal groove. Push seal ring over installer tool using Seal Pusher (J38735-3). Install remaining seal rings. Place Stator Shaft Seal Sizer (J39855-2) over stator hub and leave until oil pump installation.
7. Install pump-to-case oil seal on cover. Ensure seal is not twisted. Coat seal with ATF. Install pump-to-drum thrust washer. Ensure tangs on washer engage with holes in hub.

Scheme 27

Scheme 28

1. Remove snap ring and backing plate. Remove 3-4 clutch plates. Note number and location of parts for reassembly reference. Remove 3-4 apply plate and clutch ring retainer. (Scheme 22)
2. Remove forward clutch snap ring, and remove backing plate. Remove forward clutch sprag assembly and bearing. Remove input housing seal. Remove forward clutch plates. Note number and location of parts for reassembly reference. Remove waved and apply plates. Remove overrun clutch plates (2 steel and 2 composition). Compress overrun clutch spring retainer.
3. Remove snap ring and spring assembly. Remove overrun clutch piston and forward clutch piston. Remove seals from pistons. Note direction of seals. Remove forward clutch housing. Remove 3-4 clutch spring, 3-4 clutch apply ring and piston. Remove "O" ring from input housing. Remove turbine shaft oil seal rings.
4. Remove forward clutch race. Remove snap ring and overrun clutch hub. Remove sprag retainer and race. Note direction race is installed. Use care not to lose rollers from roller cage.

1. Inspect sprag assembly for weak or damaged springs and retainers and worn rollers. Inspect overrun clutch hub for spline damage, excessive wear and open oil passages. Inspect retainer and race for spline damage, surface wear and damaged ring grooves.
2. Replace sprag assembly if damaged. Inspect forward clutch race for spline damage, excessive wear and open oil passages. Inspect input shaft and housing for spline damage, wear and open oil passages.
3. Inspect 3 sealing check balls located in rear of turbine shaft for tightness. Turbine shaft contains one open lubrication hole. Ensure orifice cup plug is installed. Inspect turbine shaft seal areas for roughness and burrs.
4. Inspect check ball located in input housing for free operation. Inspect pistons for wear, damage and porosity. Inspect spring assemblies for damage and distortion.
5. Inspect steel and composition plates for damage. Inspect snap rings for distortion and damage. Check backing plates for flatness and distortion. Inspect clutch apply rings for distortion and damaged tangs.
6. Inspect forward clutch housing check ball for proper operation (if equipped). Inspect housing for cracks and damage in seal areas. Inspect bearings for excessive wear, flatness, damage and flat rollers.

Scheme 29

Scheme 30

Scheme 31

1. For input housing check ball replacement, drive retainer and ball assembly from housing using 1/4" diameter drift. Install NEW check ball assembly using 1/4" drift. Check ball assembly should seat on housing shoulder. Assemble forward clutch sprag assembly.
2. Install sprag assembly in forward clutch race. Notches located in sprag must face upward. (Scheme 29) Install snap ring on sprag retainer and race. Snap ring flange must face away from retainer and race.
3. Hold forward clutch race in left hand. Support sprag assembly. Install sprag retainer and race assembly in sprag assembly. (Scheme 22) Rotate sprag retainer and race assembly counterclockwise. Install remaining retainer ring. Install overrun clutch hub. Install snap ring.
4. Check sprag operation. While holding forward clutch race, rotate overrun clutch hub. Overrun clutch hub should turn freely clockwise and lock counterclockwise. (Scheme 29)
5. Place input clutch housing with turbine shaft downward. Install 3-4 piston seals with lips facing away from hub. Install 3-4 piston in input housing.
6. Install 3-4 clutch apply ring. Install "O" ring seal in input clutch housing. Install forward clutch housing. Install seals on forward clutch piston with lips facing away from tangs.
7. Install forward clutch piston in forward clutch housing. Install 3-4 spring on 3-4 clutch apply ring. Install forward clutch assembly on 3-4 spring assembly. Align forward clutch piston legs with tangs of 3-4 apply ring. Install Seal Protector (J-29883) on input housing.
8. Install 3-4 apply ring and forward clutch assembly in input clutch housing. Hold apply ring tangs while installing. DO NOT allow forward clutch piston to separate from assembly. Ensure assembly is firmly seated.
9. Install Seal Protector (J-29883) on input housing. Install overrun clutch piston with hub facing upward. If fully seated, overrun piston should be 3/16" below top of snap ring groove in input housing hub. Install spring assembly on overrun clutch piston. Compress springs, and install snap ring. Install input housing seal.
10. Install 4 overrun clutch plates, starting with steel plate. Align wide notches with case lugs. Install remaining clutch plates, alternating steel and composition plates.
11. Install bearing assembly on input clutch hub. Bearing inner race must face input housing hub. Ensure bearing is centered. Align clutch plate tabs. Install forward clutch sprag assembly in input housing. Align overrun clutch hub with clutch plates.
12. Install forward clutch apply plate in input housing. Install forward clutch waved plate. Ensure all plates are aligned with input housing tangs. Starting with steel plate, install clutch plates, alternating steel and composition plates. Install backing plate and snap ring. (Scheme 30)
13. Using 2 feeler gauges, measure clearance between backing plate and snap ring. (Scheme 31) Ensure clearance is as specified. See «FORWARD CLUTCH CLEARANCE SPECIFICATIONS»(/chevrolet/corvette/c5-1997-2004/remont/automatic-trans/#automatic-transmission-overhaul-4l60-e) table. If clearance is not as specified, install proper size backing plate with chamfered side upward. See «FORWARD CLUTCH BACKING PLATE SPECIFICATIONS»(/chevrolet/corvette/c5-1997-2004/remont/automatic-trans/#automatic-transmission-overhaul-4l60-e) table. Install snap ring. FORWARD CLUTCH CLEARANCE SPECIFICATIONS Application Clearance - In. (mm) 9.650" (245 mm) Converter.030-.069 (.76-1.75) 258 mm Converter (1) 298 mm Converter.034-.074 (.86-1.88) 300 mm Converter.034-.074 (.86-1.88) (1) Specification is not available from manufacturer. FORWARD CLUTCH BACKING PLATE SPECIFICATIONS Identification Thickness - In. (mm) A.274-.278 (6.96-7.06) B.250-.255 (6.35-6.48) C.227-.232 (5.77-5.89) D.205-.208 (5.21-5.28) E.180-.185 (4.57-4.70)
14. Install apply plate and 3-4 clutch plates. (Scheme 32) Install 3-4 clutch booster spring assemblies. (Scheme 33) Install backing plate with chamfered side upward. Install retaining snap ring. Using feeler gauge, measure clearance between backing plate and first composition plate. (Scheme 34) Clearance should be.035-.083" (.89-2.11 mm).
15. If clearance is not as specified, select proper backing plate to obtain correct clearance. See «3-4 BACKING PLATE SPECIFICATIONS»(/chevrolet/corvette/c5-1997-2004/remont/automatic-trans/#automatic-transmission-overhaul-4l60-e) table. Air check all clutches at feed holes in turbine shaft. (Scheme 35)
16. During overrun clutch test, air pressure will blow past forward clutch piston seals and exit out forward clutch feed hole in turbine shaft. Turbine shaft seals require sizing and should be installed before oil pump installation. Position Seal Installer (J-36418-1B) on input shaft. (Scheme 36) Adjustment screw in seal installer must be adjusted to obtain correct height for each seal installation. Install 4 turbine shaft seals.

3-4 BACKING PLATE SPECIFICATIONS

Scheme 32

Scheme 33

Scheme 34

Scheme 35

Scheme 36

Remove snap ring from reverse input clutch housing. Remove selective backing plate, steel plates, composition plates and Belleville plate. (Scheme 22) Note number of clutch plates for reassembly reference. Compress reverse input clutch spring assembly. Remove retainer ring and spring assembly. Remove piston and seals.

Inspect all plates for damage, distortion, flatness and burred edges. Inspect spring retainer for distortion. Check piston for deformation or damage. Inspect clutch housing bushings for wear. Inspect clutch housing for dishing. Replace worn or damaged parts as necessary.

Note. Soak clutch plates in ATF before installation.

1. Apply ATF to piston seals. Install seals on piston with seal lips facing away from plates. Install piston in clutch housing. Install spring assembly with large opening toward piston. Compress spring assembly. Install retainer ring. CAUTION: Ensure correct retainer ring is used. Ensure reverse input clutch retainer ring is not interchanged with low-reverse retainer ring.
2. Install Belleville plate with inner diameter facing up. Install clutch plates starting with steel plate and alternating with composition plate. Install backing plate with chamfered side upward. Install snap ring. Apply even pressure to backing plate using fingers. (Scheme 37)
3. Do not apply too much pressure or Belleville plate will be distorted. Using feeler gauge, measure clearance between snap ring and backing plate. Clearance should be.040-.076" (1.02-1.93 mm). Select backing plate. See «REVERSE INPUT CLUTCH BACKING PLATE SPECIFICATIONS»(/chevrolet/corvette/c5-1997-2004/remont/automatic-trans/#automatic-transmission-overhaul-4l60-e) table.

REVERSE INPUT CLUTCH BACKING PLATE SPECIFICATIONS

Scheme 37

LOW-REVERSE SUPPORT ASSEMBLY

Disassembly & Inspection

Remove inner race and snap ring. Remove roller clutch assembly. Check inner race for damage and surface finish. (Scheme 38) Inspect roller and springs for damage and distortion. Inspect support for loose cam, cracks and damaged surface finish. Replace damaged parts as necessary.

1. Install roller clutch assembly in low-reverse support. (Scheme 38) Place support in case with hub facing downward. Install inner race. Rotate inner race while pushing downward. Use care not to damage roller and springs during installation.
2. Ensure inner race is fully seated. Bottom tangs will be flush with carrier hub when fully seated. Inner race should rotate clockwise and lock counterclockwise with clutch hub downward. Insert support retainer spring into case between case lug and open notch in support.

Scheme 38

1. Remove 4th apply piston and housing from 2nd apply piston assembly. Remove return spring from apply pin. Install Piston Compressor (J-22269-01) on 2nd apply piston. (Scheme 40)
2. Compress 2nd servo apply piston assembly. Remove retainer ring. Separate 2nd apply piston, spring and retainer. Remove retainer ring, washer and spring from apply pin, and remove pin. Remove all oil seal rings. (Scheme 39)

Scheme 39

Scheme 40

Inspect all pistons for porosity and damage. Check for ring groove damage and servo bore in case for any wear which may cut servo seals. Check all springs and oil seal rings for distortion and damage.

Different servo piston housings and 2nd apply pistons are used for different applications. If servo piston housing or 2nd apply piston is replaced, inside dimension of parts must be checked. Measure inside diameter of piston housing and 2nd apply piston. Dimension must be same as original. To reassemble, reverse disassembly procedure. Coat seals with petroleum jelly before assembly.

Note. Valves are held in valve body by pins or retainers. Valves may be under spring pressure. Note location of all parts during disassembly for reassembly reference.

Remove valve train, and note direction of valve installation. (Scheme 41) Remove all valve pins, retainers and bore plugs. Remove shift solenoids. Note locations of all parts.

Inspect valves and sleeves for scoring and cracks. Ensure valves move freely in bores. Inspect valve body for cracks and scored bores. Inspect machined surfaces for damage. Inspect springs for damaged coils. Replace damaged parts as necessary.

For reassembly, reverse disassembly procedure. Ensure all parts are installed in correct location. (Scheme 41) Ensure pins, retainers and bore plugs are fully installed and do not extend into machined areas.

Scheme 41

Cleaning & Inspection

Clean transmission case and dry with compressed air. Inspect case assembly for damage, cracks and damaged bolt hole threads. Inspect valve body surface for flatness and land damage. Check case oil passages for restrictions and blockage. Blow compressed air through all case passages. (Scheme 42) Inspect case internal clutch plate lugs for damage and wear. Inspect servo and accumulator bores for damage. Inspect all snap ring grooves for damage.

Scheme 42

1. Clean all parts and dry with compressed air. Inspect reaction and input carriers for pinion gear damage, excessive wear and improper staking of pinion pins. Inspect carrier bearings for heat damage, flatness and roller condition. Place output shaft sleeve inside reaction carrier and input carrier.
2. Rotate sleeve and note smoothness of bearing operation. Replace carrier assembly if roughness is felt. Check pinion gear end play on reaction and input carriers. (Scheme 43)
3. Pinion gear end play should be.008-.024" (.20-.61 mm). Inspect internal reaction gear and support for cracks and damaged splines. Inspect low-reverse clutch plates for wear and signs of excessive heat.
4. Inspect low-reverse clutch piston for roughness or damage in seal ring area. Inspect retainer ring and spring assembly for damage. Inspect sun and internal gears and supports for spline and bushing wear and damage. Replace damaged parts as necessary.

Scheme 43

Clean all parts and dry with compressed air. Inspect 1-2 and 3-4 accumulator parts for damage to pistons or housing. Inspect for flatness and condition of accumulator, oil passage plate and gasket. Inspect wiring harness leads and connectors for damage. Inspect speed sensor rotor teeth for damage and distortion.

TRANSMISSION REASSEMBLY

Note. To identify bushing, seal, thrust bearing and thrust washer locations and direction, refer to appropriate illustration. (Scheme 49)and (Scheme 50).

1. Place transmission in a vertical position. Install seals on low-reverse clutch piston. Apply petroleum jelly to seals. Align and install piston with notch in bottom of transmission case. Ensure piston is fully seated and parking pawl aligns with opening in piston wall. Install spring assembly with flat side of retainer upward. Compress springs and install retainer ring.
2. Coat bearing assembly with petroleum jelly. Install bearing assembly on case hub with outside bearing race toward case hub. Install internal reaction gear and support. Install bearing assembly onto support with outside bearing race toward support. Install oil deflector (if equipped) and reaction carrier assembly in case. (Scheme 22)
3. Place waved plate on work bench. Install 5 composition plates and 4 steel plates alternately, starting with composition plate. Install low-reverse support. Apply light pressure to low-reverse support. Do not flatten waved plate. Measure height of clutch pack from work bench to top of low-reverse support. (Scheme 44)
4. Using height dimension, determine proper selective spacer plate to be used. See «SPACER PLATE SELECTION»(/chevrolet/corvette/c5-1997-2004/remont/automatic-trans/#automatic-transmission-overhaul-4l60-e) table. SPACER PLATE SELECTION Measured Clutch Pack Height - In. (mm) (1) Identification Plate Thickness - In. (mm) 1.084-1.105 (27.53-28.07) None.066-.072 (1.67-1.85) 1.105-1.125 (28.07-28.58) "0".046-.052 (1.17-1.31) 1.064-1.084 (27.03-27.53) "1".087-.092 (2.19-2.34) (1) Clutch pack height is measured without spacer plate in position.
5. Place spacer plate between waved plate and first composition plate with identification facing upward. Measure overall height of clutch pack. Overall height should be 1.15-1.18" (29.2-29.9 mm). Install low-reverse clutch pack into transmission case. Ensure clutch plates align with splines of reaction carrier. Ensure steel plates are properly indexed in transmission case. (Scheme 45)
6. Install low-reverse support in case with hub downward. Install inner race by pushing downward while rotating until it is fully engaged. Bottom tangs will be flush with hub when fully installed. Install spring retainer in case between case lug and open notch in support. Install low-reverse snap ring.

Scheme 44

Scheme 45

REACTION & INPUT GEAR SETS

1. Install retainer ring on reaction sun gear (if removed). Install sun gear into reaction carrier. Install thrust washer on low-reverse clutch race. Install reaction sun gear shell on reaction sun gear.
2. Install thrust washer on reaction sun gear shell. Ensure thrust washer tangs engage on gear shell. Install input internal gear and reaction carrier shaft in sun gear shell. Carrier shaft splines must engage with reaction carrier. (Scheme 22)
3. Install thrust washer on reaction carrier shaft. Outer race must face toward reaction carrier shaft. Install output shaft in transmission. Ensure output shaft engages with all parts.
4. Install Output Shaft Support (J-29837-A). (Scheme 17) Adjust support so output shaft is positioned upward as far as possible. Install input carrier (planetary) assembly with hub end down on output shaft. Install NEW retainer ring on output shaft. Remove output shaft support. Install input sun gear, indexing gear end with input carrier pinions.

REVERSE INPUT ASSEMBLY & INPUT CLUTCH

1. Install selective thrust washer on input housing. Install bearing assembly on selective thrust washer. Inner race (Black) must go toward oil pump. Position reverse input assembly on input clutch assembly. Reverse input clutch plates must align with input clutch hub. Ensure all clutch plates are fully engaged.
2. Install reverse and input clutch assemblies in transmission case as an assembly. Align 3-4 clutch plates of input assembly with input internal gear. Assembly is fully seated when reverse input clutch housing is just below oil pump face of case.

OIL PUMP ASSEMBLY

1. Ensure turbine shaft seals on input shaft have been sized using Seal Sizer (J-36418-2A). (Scheme 36) Install aligning pins in 2 opposing pump bolt holes in transmission case. Ensure thrust washer is installed on rear of oil pump. Thrust washer can be retained using petroleum jelly.
2. Remove input shaft Seal Sizer (J-36418-2A). Remove Stator Shaft Seal Sizer (J39855-2). Install oil pump into case, aligning filter and pressure regulator holes with holes in case. Install retaining bolts. Tighten bolts to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/corvette/c5-1997-2004/remont/automatic-trans/#automatic-transmission-overhaul-4l60-e__torque-specifications). Place transmission in a horizontal position.
3. Turbine shaft should rotate by hand. If turbine shaft will not rotate, loosen pump retaining bolts and attempt to rotate shaft again. If shaft now turns, reverse and input assemblies have not been indexed properly or some other assembly problem has occurred, such as thrust washer not positioned properly.
4. Check transmission end play. See «TRANSMISSION END PLAY CHECK»(/chevrolet/corvette/c5-1997-2004/remont/automatic-trans/#automatic-transmission-overhaul-4l60-e__transmission-end-play-check). Transmission end play should be.005-.036" (.13-.91 mm). Install torque converter. Ensure converter hub is aligned with oil pump. Install torque converter retaining strap to hold converter.

2-4 BAND & SERVO ASSEMBLY

1. Install 2-4 band in case. Align band anchor pin end with case pin hole. Install band anchor pin in case. (Scheme 19) Ensure band anchor pin aligns with end of 2-4 band.
2. Install 2-4 servo assembly into case, and index apply pin on band end. Check for proper engagement of apply pin on band end. Recheck 2-4 servo apply pin selection to ensure correct pin is installed.
3. Remove 4th apply piston and return spring. (Scheme 39) Remove retainer ring, washer, apply pin spring and 2nd apply pin. Install Piston Compressor (J-22269-01) on 2nd apply piston. (Scheme 40)
4. Remove retainer ring, cushion spring and spring retainer. Install Band Apply Pin Tool (J-33037) and apply pin. (Scheme 46) Apply 100 INCH lbs. (11 N.m) torque.
5. White line on band apply tool should be within gauge slot if pin length is correct. If White line is not within gauge slot, inspect 2-4 band and reverse input drum for wear and damage during disassembly.
6. Servo pin length must be checked during reassembly. Servo pin is preset and must not be readjusted. Different length servo pins are available. See «SERVO PIN SPECIFICATIONS»(/chevrolet/corvette/c5-1997-2004/remont/automatic-trans/#automatic-transmission-overhaul-4l60-e) table. Select proper length servo pin. Reassemble 2-4 servo. Install servo cover and "O" ring. Compress cover and install cover retaining ring. Index ends of retaining ring with slot in case.

SERVO PIN SPECIFICATIONS

Scheme 46

TRANSMISSION END PLAY CHECK

1. Install Pump Remover/End Play Fixture (J-24773-A) and End Play Adapter (J-25022-A) on end of turbine shaft. (Scheme 47) Clamp dial indicator on long bolt with indicator tip on end play fixture. Zero dial indicator.
2. Pull up on end play fixture. Measure transmission end play. Transmission end play should be.005-.036" (.13-.91 mm). If transmission end play is not within specification, selective thrust washer must be changed between oil pump and input housing. (Scheme 22) Install appropriate thrust washer, and recheck end play. See «OIL PUMP THRUST WASHER SPECIFICATIONS»(/chevrolet/corvette/c5-1997-2004/remont/automatic-trans/#automatic-transmission-overhaul-4l60-e) table.

OIL PUMP THRUST WASHER SPECIFICATIONS

Scheme 47

1. Install 3-4 accumulator piston pin in case. Install 3-4 piston seal on piston. Install 3-4 accumulator piston on pin. Legs of piston must face valve body.
2. Install 3-4 accumulator spring. Install oil screens in proper locations. (Scheme 48) (Scheme 15)for check ball and filter installation locations. Install alignment pins in transmission case to aid spacer plate and valve body installation. Install spacer plate gasket and spacer plate. Install spacer plate support.
3. Install 1-2 accumulator spring, oil seal ring and 1-2 accumulator piston. Install accumulator cover and bolts. Tighten bolts to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/corvette/c5-1997-2004/remont/automatic-trans/#automatic-transmission-overhaul-4l60-e__torque-specifications).
4. Coat check balls with petroleum jelly. Install check balls in proper locations in valve body. (Scheme 14)and (Scheme 15). Install manual valve link. Ensure manual valve link is properly seated in manual valve. (Scheme 13) Improper positioning may prevent vehicle operation in "D" range. NOTE: Improper positioning of throttle valve link will result in erratic shift points or high oil pressure.
5. Install valve body and retaining bolts. Ensure correct length and location of bolts. (Scheme 12) Install detent spring. Install detent spring bolt. Install transmission fluid pressure manual valve position switch. Install TCC solenoid. Install valve body bolts that secure wiring harness. Tighten all valve body bolts to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/corvette/c5-1997-2004/remont/automatic-trans/#automatic-transmission-overhaul-4l60-e__torque-specifications).
6. Install TCC PWM solenoid. Install retainer clip. Install electrical connectors to switches and solenoids. (Scheme 11) Install oil filter and "O" ring. Install transmission oil pan.

Scheme 48

1. Install speed sensor rotor retaining clip on output shaft. Install "O" ring in output shaft sleeve. Install output shaft sleeve on output shaft. DO NOT position output shaft sleeve past machined surface of output shaft. Install seal ring on extension housing.
2. Position extension housing on transmission case. Install retaining bolts. Install oil seal in extension housing. Install speed sensor assembly. Install retainer and bolt. Tighten bolt to specification. Install outside electrical connector. Install PNP switch and manual shift lever. See «PARK/NEUTRAL POSITION SWITCH»(/chevrolet/corvette/c5-1997-2004/remont/automatic-trans/#automatic-transmission-overhaul-4l60-e__parkneutral-position-switch) under REMOVAL & INSTALLATION.

Scheme 49

Scheme 50

TORQUE SPECIFICATIONS

TORQUE SPECIFICATIONS

TRANSMISSION SPECIFICATIONS

TRANSMISSION SPECIFICATIONS

See also:
• MODEL IDENTIFICATION
• REMOVAL & INSTALLATION
• ROAD TEST
• HYDRAULIC PRESSURE TESTS
• CLUTCH & BAND APPLICATIONS
• TORQUE CONVERTER DIAGNOSIS
• TROUBLE SHOOTING
• TORQUE SPECIFICATIONS
• LUBRICATION
• TRANSMISSION END PLAY CHECK
• PARK/NEUTRAL POSITION SWITCH