Automatic Transaxle Overhaul & Testing - 4T40-E: Other Oldsmobile Cutlass VI

ON-VEHICLE SERVICE

The following components can be serviced without removing transaxle from vehicle

1. Case Side Cover
2. Converter-To-Flexplate Bolts
3. Cooler Lines
4. Drive Axles
5. Low And Reverse Servo
6. Intermediate/4th Servo
7. Shift Control Cable
8. Pressure Switch Assembly
9. Pressure Control Solenoid
10. TCC Control Solenoid
11. Speed Sensor
12. Transaxle Oil Pan
13. Transaxle Filter
14. Control Valve Assembly
15. Wiring Harness
16. 1-2 Or 3-4 Shift Solenoids
17. Accumulator Assemblies

VALVE BODY

See OIL PUMP & CONTROL VALVE ASSEMBLY under TRANSAXLE DISASSEMBLY.

DRIVE AXLE SHAFTS

See AXLE SHAFT article in the DRIVE AXLE section.

QUICK CHECK

1. Check level and condition of transaxle fluid. Check PCM memory for stored trouble codes. See AUTO TRANS DIAGNOSIS - 4T40-E article in the AUTOMATIC TRANSMISSIONS section. If no trouble codes are present, go to next step. If codes are present, diagnose and repair all PCM-related trouble codes. Clear PCM trouble code memory.
2. Perform road test. See «ROAD TEST»(ref-124186-S13771586272001100100000) under TESTING. During road test, record shift points. If shift point timing or shifting is incorrect, go to AUTO TRANS DIAGNOSIS - 4T40-E article.
3. If shift(s) is too harsh or too soft, see «HYDRAULIC PRESSURE TEST»(ref-124186-S40955795642001100100000) under TESTING. For specific complaints, see appropriate condition(s) listed under SYMPTOM DIAGNOSIS.

Oil Out Of Vent Or Foaming

Transaxle overfilled. Oil contaminated with antifreeze or engine overheating. Drain back holes plugged. Case porosity, incorrect fluid level indicator, plugged vent or misalignment of oil pump-to-case gasket (if equipped).

High Or Low Line Pressure

Incorrect oil level. Stuck pressure regulator valve, torque signal regulator valve, boost valve or springs. Damaged pressure control solenoid, throttle position sensor, oil pump or oil pump drive shaft. Pressure relief valve spring damaged or ball missing. Leaking cooler lines, oil filter seal or pressure control solenoid "O" ring.

Inaccurate/Inconsistent Shift Points

Electrical malfunction in throttle position, input speed or vehicle speed sensor circuit. Damaged or disconnected sensor.

Harsh Shifts

High line pressure. Missing check balls, binding accumulator springs or piston, accumulator valve stuck. Plugged clutch housing retainer and ball assemblies.

No Reverse Or Slips In Reverse

Reverse clutch does not apply or is slipping. Reverse clutch piston and seal assembly binding, cracked or leaking. Clutch friction plates worn or splines broken. Reverse clutch snap ring out of position. Clutch housing cracked, feed holes plugged or tangs broken. Housing retainer and ball assembly missing or out of position. Clutch springs binding. Driven sprocket support seal rings leaking. Channel plate and gasket misaligned, damaged or fluid restriction. Fluid leak across channels.

Low and reverse band and servo does not apply or is slipping. Servo piston broken or binding, servo piston seals leaking, servo pin and springs binding. Servo cover broken, loose or leaking. Low and reverse band broken, worn or out of position. Anchor pin broken. Oil feed tubes broken, bent, plugged or leaking. Transaxle case porosity, fluid leak or restriction. Shift linkage, manual valve and linkage disconnected or misaligned. No. 1 check ball missing. Low fluid level or pressure.

No First Gear Or Slips In First Gear

Forward clutch does not apply or is slipping. Clutch piston and seal assembly cracked, leaking or binding. Inner seal orifice plugged. Clutch friction plates worn or splines broken. Snap ring out of position. Clutch housing cracked or feed holes plugged. Housing retainer and ball assembly missing or out of position. Springs binding. Input sprag or low roller clutch damaged or not holding.

Fluid leak or restriction. Oil feed tubes broken, bent, plugged or leaking. Forward clutch support seal rings leaking, damaged or feed holes plugged. Channel plate and gasket misaligned, fluid leak across channels or restriction. Pressure switch assembly "O" ring leaking. 1-2 shift solenoid failed off or leaking. 1-2 shift valve stuck in upshift position. 2-3 shift solenoid failed on or exhaust is plugged. Manual valve or shift linkage is misaligned. Torque converter stator roller clutch does not hold. Low line pressure.

No Second Gear Or Slips In Second Gear

2nd clutch does not apply or is slipping. Clutch piston and seal assembly cracked, leaking or binding. Clutch friction plates worn or splines broken. Snap ring out of position. Driven sprocket support damaged or leaking. Springs binding.

Fluid leak or restriction in 2nd clutch. Misaligned, loose or restricted valve body, gaskets and spacer plate, channel plate and gasket, and driven sprocket support. 2nd roller clutch damaged or does not hold. 1-2 shift solenoid stuck on or plugged. 1-2 accumulator piston leaking. 1-2 accumulator valve stuck. 2-3 shift valve stuck in upshift position. Pressure switch assembly malfunction. Low line pressure.

2nd Gear Only

1-2 shift valve stuck in downshift position.

No Third Gear Or Slips In Third Gear

Direct clutch does not apply or is slipping. Clutch piston and seal assembly cracked, leaking or binding. Clutch friction plates worn or splines broken. Snap ring out of position. Direct clutch and coast housing and input shaft damaged, cracked or feed holes plugged. Housing retainer and ball assembly missing or out of position. Springs binding.

Direct clutch fluid leak or restriction. Misaligned, loose or restricted valve body, gaskets and spacer plate, channel plate and gasket, and driven sprocket support. Driven sprocket support seals leaking or input shaft seals leaking. Damaged or misaligned sleeve. 2-3 shift solenoid stuck off or leaking. 2-3 accumulator piston leaking. 2-3 accumulator valve stuck. 3-4 shift valve stuck in upshift position. Pressure switch assembly malfunction. Low line pressure.

No Fourth Gear Or Slips In Fourth Gear

Intermediate/4th band and servo does not apply or is slipping. Servo piston broken or binding, servo piston seals leaking, servo pin and springs binding. Servo cover broken, loose or leaking. Intermediate/4th band broken, worn or out of position. Transaxle case cracked at band seat.

Misaligned, loose or restricted valve body, gaskets and spacer plate, channel plate and gasket. 1-2 shift solenoid stuck off or leaking. Manual valve misaligned. 3-4 accumulator piston leaking. 3-4 accumulator valve stuck. 3-4 shift valve stuck in downshift position. Pressure switch assembly malfunction. Low line pressure. Direct clutch malfunction.

Loss Of Drive

Damaged torque converter or axle shafts. Oil pump seized or broken gears. Oil filter plugged or seal missing. Low fluid level. Shift linkage disconnected. Drive or driven sprockets and drive chain broken. Planetary (carrier) gear or final drive malfunction. Channel plate and gasket, valve body, gaskets and spacer plate damaged, leaking or misaligned. Damaged forward sprag clutch, forward clutch or low roller clutch does not hold. Fluid leaks.

Loss Of Power

Low fluid level. Failed shift solenoids. TCC stuck on or dragging. Damaged torque converter.

Engine Stall

TCC stuck on or dragging. TCC solenoid stuck on or solenoid exhaust plugged. TCC regulated apply valve stuck in apply position.

No Engine Braking In All Manual Ranges

Coast clutch does not apply or is slipping. Clutch piston and seal assembly leaking, cracked or binding. Clutch friction plates worn or splines broken. Clutch springs binding. Direct and coast clutch housing and input shaft damaged, cracked or fluid feed holes restricted. Housing retainer and ball assembly loose or missing.

Coast clutch fluid leak or restriction. Misaligned, loose or restricted valve body, gaskets and spacer plate, channel plate and gasket, and driven sprocket support. Driven sprocket support seals leaking or input shaft seals leaking. Damaged or misaligned sleeve. 3-4 shift valve stuck in 4th gear position. Manual valve and linkage misaligned.

No Engine Braking In Manual Second

Coast clutch does not apply or is slipping. Intermediate/4th band slipping or does not apply. Pressure switch assembly leaking or inoperative. Incorrect vehicle speed sensor reading (reads zero MPH).

No Engine Braking In Manual First

Coast clutch does not apply or is slipping. Low and reverse band does not apply or is slipping. Pressure switch assembly leaking or inoperative. No. 1 check ball missing.

Drives In Neutral

Forward clutch not releasing. Reverse clutch and low and reverse servo do not release. Manual valve and linkage misaligned.

No TCC Or TCC Slipping

TCC solenoid stuck off, "O" ring leaking, no voltage to solenoid or poor connection. No signal to solenoid from PCM. Brake switch not functioning. Stuck pressure regulator valve. Torque converter internal failure. TCC fluid circuit leaks or plugged release exhaust orifice. TCC regulated apply valve and TCC control valve stuck in TCC release position. Stuck TCC feed limit valve. Low fluid level or pressure. Plugged cooler lines.

No TCC Release

TCC solenoid internal failure, fluid exhaust plugged or external ground. Torque converter internal failure. TCC regulated apply valve and TCC control valve stuck in TCC apply position.

TCC Apply With Cold Engine

Engine coolant temperature sensor malfunction. TCC circuit malfunction.

Transaxle Locked In Reverse

Damaged parking pawl binding on final drive internal gear.

Vehicle Moves In Park

Manual linkage damaged or disconnected. Broken parking pawl spring, parking pawl or park lock gear in final drive internal gear assembly. Parking actuator damaged.

Scheme 61

CLUTCH & BAND APPLICATION CHART

Gear Selector Position "D" (Overdrive)

1. With gear selector in "D" (overdrive) position, choose throttle position angle of 10 or 25 percent. (Scheme 62)or (Scheme 63). Set scan tool to monitor throttle position angle and vehicle speed. Accelerate vehicle to chosen throttle position angle and hold throttle steady.
2. Note shift speed engagement points in 2nd gear, 3rd gear and overdrive gear. Use chart as a reference for proper shift speeds. (Scheme 62)or (Scheme 63). Also note Torque Converter Clutch (TCC) engagement point while in Overdrive. Repeat procedure using different throttle position angle. NOTE: Shift speeds may vary due to slight hydraulic delays responding to electronic controls. A change from original equipment tire size also affects shift speeds. Ensure TCC engages in overdrive. TCC should not apply unless transaxle has reached a minimum operating temperature of 46°F (8°C) and engine coolant temperature is 122°F (50°C).
3. At vehicle speeds of 40-50 MPH in overdrive, quickly increase throttle position angle to more than 50 percent. Verify TCC releases, transaxle immediately downshifts to 3rd gear, 1-2 shift solenoid turns off and 2-3 shift solenoid remains on.
4. At vehicle speeds of 40-50 MPH in overdrive, quickly depress accelerator to wide open position (full throttle detent downshift). Verify TCC releases, transaxle immediately downshifts to 2nd gear and both solenoids are off.
5. At vehicle speeds of 40-55 MPH in overdrive, release accelerator pedal while moving gear selector to "3" (third gear) position. Verify TCC releases, transaxle immediately downshifts into 3rd gear, and engine braking slows vehicle.
6. Move gear selector to "D" (overdrive) position, and accelerate to 40-45 MPH. Release accelerator pedal while moving gear selector to "2" (2nd gear) position. Verify TCC releases, transaxle immediately downshifts to 2nd gear, and engine braking slows vehicle.
7. Move gear selector to "D" (overdrive) position, and accelerate to 40 MPH. Release accelerator pedal while moving gear selector to "1" (1st gear) position. Verify TCC releases, transaxle immediately downshifts to 2nd gear and engine braking slows vehicle. At speeds below 37 MPH, transaxle immediately downshifts to 1st gear. NOTE: A manual 1st-3rd gear ratio will occur at high speeds as an upshift safety feature. DO NOT attempt to perform this shift.
8. With gear selector in the "D" (overdrive) position, accelerate vehicle to overdrive gear with TCC applied. Release accelerator pedal, and lightly apply brakes. Verify TCC releases and downshifts occur at speeds shown in shift speed chart. (Scheme 62)or (Scheme 63).

Scheme 62

Scheme 63

Note. Upshifts in manual gear ranges are controlled by shift solenoids. Perform following steps by accelerating vehicle at throttle position angle of 10 percent.

Gear Selector Position "3" (3rd Gear)

With vehicle stopped, move gear selector to "3" (3rd gear) position and steadily increase throttle pressure to accelerate vehicle. Note speeds at which vehicle shifts into 2nd and 3rd gears. (Scheme 62)or (Scheme 63).

Gear Selector Position "2" (2nd Gear)

With vehicle stopped, move gear selector to "2" (2nd gear) position. Accelerate vehicle and note speed at which vehicle shifts from 1st gear to 2nd gear. Accelerate vehicle to 25 MPH. Verify transaxle does not shift into 3rd gear, and TCC does not apply.

Gear Selector Position "1" (1st Gear)

With vehicle stopped, move gear selector to "1" (1st gear) position. Accelerate vehicle to 20 MPH. Verify transaxle does not upshift, and TCC does not apply.

Gear Selector Position "R" (Reverse)

With vehicle stopped, move gear selector to "R" (Reverse) position. Verify 1-2 shift solenoid is on, and 2-3 shift solenoid is off.

Brake Switch

Power from ignition switch passes through brake switch to TCC solenoid. When brake pedal is depressed with TCC applied, power to TCC solenoid is interrupted, releasing converter clutch and preventing engine from stalling.

Engine Coolant Temperature (ECT) Sensor

This sensor provides PCM with engine coolant temperature information. PCM will not allow TCC operation until signal from this sensor indicates coolant temperature more than 130-150°F (55-65°C).

Powertrain Control Module (PCM)

To determine application of torque converter clutch, PCM receives and processes information from various input devices. These devices may include vehicle speed sensor, engine coolant temperature sensor, throttle position sensor and brake switch. PCM controls application of torque converter clutch by providing a ground circuit for TCC solenoid circuit.

TCC Solenoid

Solenoid is energized by PCM to redirect transaxle fluid to converter clutch apply valve in control valve assembly. TCC solenoid controls apply and release of TCC.

Throttle Position (TP) Sensor

Sensor provides PCM with throttle position information. TCC operation is prevented when throttle position signal is less than a specified value.

Vehicle Speed Sensor (VSS)

This sensor sends vehicle speed information to PCM. Vehicle speed must be more than a certain value before TCC can be applied. A Permanent Magnet (PM) generator type sensor is mounted on transaxle.

Note. Diagnostic codes for engine coolant temperature sensor and throttle position sensor may be present while performing TCC electrical diagnosis. See appropriate article in the ENGINE PERFORMANCE section for complete diagnostic information for these codes.

REAR SECTION

1. Thoroughly clean transaxle exterior. Drain fluid, and remove torque converter. Remove input shaft "O" ring from input shaft. Place transaxle in holding fixture. Remove and discard snap ring from end of axle stub shaft. Attach slide hammer to shaft removal tool.
2. Install shaft removal tool into snap ring groove on stub shaft. Secure removal tool to stub shaft. Pull on stub shaft and rotate until stub shaft snap ring at differential seats in taper on differential side gear. Pull stub shaft out using slide hammer.

LOWER SECTION

1. Rotate transaxle so case side cover is facing upward to drain most transaxle fluid through stub shaft end of transaxle. Rotate transaxle with oil pan facing up. Remove speed sensor stud, speed sensor and "O" ring. Remove bottom oil pan and gasket. Remove oil filter and filter seal from transaxle case. (Scheme 64)
2. Remove oil level control valve. Remove 4 oil feed tube bolts and oil feed tube assembly. Feed tube seal rings are glued in place and should remain with feed tube assembly. Seal rings are reusable.

Scheme 64

CASE SIDE COVER

Rotate transaxle so case side cover is facing up. Remove 10 side cover bolts and one stud. Remove transaxle side cover. Remove 2 side cover gaskets and side cover-to-driven sprocket support thrust washer. Components may be removed with side cover. (Scheme 64)

CHANNEL PLATE, GASKET & ACCUMULATORS

Disconnect manual valve clip and link from manual valve. (Scheme 65)

Remove 10 channel plate bolts. see scheme 7 Remove channel plate assembly with drive sprocket-to-channel plate thrust washer, accumulator pistons and pins, manual valve and detent lever spring and bolt. Remove and discard channel plate-to-case gasket. Remove 3 accumulator springs from case. (Scheme 66)

Scheme 65

Scheme 66

OUTPUT SHAFT SLEEVE

Note. Output shaft cannot be removed without complete disassembly of transaxle. Attempting to remove output shaft at this time in same manner as stub shaft will result in damage to other transaxle components.

Using sleeve puller, remove and discard output shaft sleeve. Sleeve is not reusable after removal. Position puller leg's under sleeve. Tighten center bolt down to pull sleeve off shaft. (Scheme 67)

Scheme 67

LEFT & RIGHT AXLE SEALS

Note. Seal Installer (J-41102) must be used to install axle seals. Installer sets seal depth during installation.