Automatic Transaxle Overhaul & Testing - 4T60-E: Diagnosis Oldsmobile Eighty-Eight X

TROUBLE SHOOTING

Note. For testing and diagnostic procedures of electronic components, see AUTO TRANS DIAGNOSIS - 4T60-E - 1995 article or AUTO TRANS DIAGNOSIS - 4T60-E - 1996 article.

Note. For clutch and band applications, see CLUTCH & BAND APPLICATION CHART table.

SYMPTOM DIAGNOSIS

Note. PCM controls TCC, PWM solenoid (if equipped) and shift solenoids "A" and "B".

ELECTRONIC SELF-DIAGNOSTICS & ELECTRONIC TESTING

Note. See AUTO TRANS DIAGNOSIS - 4T60-E - 1995 article or AUTO TRANS DIAGNOSIS - 4T60-E - 1996 article in AUTOMATIC TRANSMISSIONS.

ROAD TEST

Note. Before road testing vehicle, engine and transaxle must be at operating temperature. Torque converter clutch will not engage if engine coolant has not reached operating temperature.

Inspection

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. Crankshaft Pilot Broken Or Damaged
5. Hub Scored Or Damaged
6. Stator Failure
7. Torque Converter Imbalance
8. Engine Coolant Contamination
9. Excessive End Play

Cleaning & Inspection

Clean transaxle case thoroughly with solvent, and then air dry. Inspect transaxle case for damage to band lugs, snap ring grooves and drive sprocket bearings. Check for interconnected or damaged oil passages and servo bores. Inspect case for stripped threads in bolt holes or casting porosity. Repair or replace case if necessary.

Disassembly & Inspection

1. Inspect final drive internal gear for damaged teeth, worn bearing surfaces, broken parking pawl spring or damage to parking pawl. Inspect sun gear, thrust bearings, parking gear and speed sensor rotor for wear or damage.
2. Check final drive carrier pinion gears for excessive end play. Use a feeler gauge and measure end play between carrier and pinion gear thrust washer. End play should be.009-.025" (.24-.63 mm).
3. Using a pin punch, drive differential pinion shaft retainer pin from carrier. Remove pinion shaft, pinion and side gears, and thrust washers. (Схема №13) Inspect all parts for damage or abnormal wear. Inspect final drive sun gear shaft for damaged splines or journals.

Inspection & Reassembly

Inspect final drive sun gear shaft for damaged splines or journals. (Схема №30) Install thrust bearing. Install final drive sun gear shaft into final drive, ensuring splines engage with parking gear and sun gear.

DO NOT wash bands in solvent. Inspect 1-2 and forward band assembly for heat damage, lining cracks and separation. Check band stop for damage and replace if necessary.

Inspect reaction carrier and reaction drum for damaged teeth, scoring or warpage. Check thrust bearing for damage. Using a feeler gauge, check reaction carrier pinion gear end play. End play should be .009-.030" (.23-.77 mm). Check for damage to reaction carrier internal gear.

Check input carrier pinion gears for proper end play. Pinion gear end play should be .009-.030" (.23-.77 mm). Inspect internal gear and pinion gears for worn or damaged teeth, and ensure pinions rotate freely. Inspect thrust bearing for damage (thrust bearing cannot be removed from carrier).

Inspect reverse reaction drum for damaged teeth and distortion. Install reverse reaction drum, ensuring spline teeth engage input carrier. DO NOT wash reverse band in solvent. Inspect reverse band assembly for damage and replace if necessary.

Inspect 3rd sprag outer race for scoring and wear. Inspect assemblies for damaged rollers and springs. Install any loose roller by depressing spring and inserting roller. Inspect input sprag inner and outer races for damage. Check sprag assembly for damaged sprags or cages. Check sprag cage for distortion or broken tabs. Inspect input sun gear splines and bushing for damage.

Inspect all clutch plates for cracks, wear, lining separation, pits or other signs of damage. Inspect thrust washer for damage. Inspect input clutch housing and shaft for interconnected oil passages, damaged clutch hub, worn bushings, or damaged 3rd clutch shaft seal or oil seal rings.

1. Inspect steel and composition plates for wear, lining separation, pitting or damage. Inspect apply ring and spring return for damage. Inspect piston and piston seals for damage.
2. Inspect 2nd clutch housing for damaged inner piston seal. Inspect for damaged bushings and spline teeth. Check for scored band surface. Check retainer and ball assembly for damage. Inspect housing for warpage.

Inspect driven sprocket support for worn or damaged oil seal rings. Check bushing and piston seal surface for damage. Check for blocked or interconnected oil passages and cup plug. Check chain scavenging scoop and baffle for cracks. Inspect piston, seals and thrust washer for damage. Check spring retainer for distorted springs. Inspect driven sprocket bearing for damage.

Inspect output shaft snap ring groove, splines, journal and bearings for damage. Replace if necessary.

Inspect drive and driven sprockets for damaged or chipped teeth. Pull drive link chain toward transaxle case. Measure distance between drive link chain and transaxle case. Replace drive link chain if measurement is less than 1/8". Check sprockets for damaged bearing surfaces or splines. Check thrust washers and drive link for excessive wear or damage. Inspect 4th clutch shaft and turbine shaft for damaged bushings, splines or seals. Replace if necessary.

Clean valves, springs and bushings in solvent. DO NOT use shop rags to clean valve body components. Inspect valves and bushings for scoring, nicks and scratches. Inspect springs for damaged or distorted coils. Inspect valve body casting for porosity, interconnected oil passages and damaged machined surfaces.

1. Inspect pump body for porosity, interconnected oil passages, or damaged inner pump area surface or machine facing. Check slide, springs, rotor and vanes for damage. Inspect slide seal, slide support and seals for damage. (Схема №9)
2. Measure undamaged area of rotor, vane or slide to check for proper size. See «OIL PUMP COMPONENT THICKNESS»(ref-25523-S25213789392001011700000). (Схема №21) En sure replacement parts are matched to fit within specification.

Note. Oil pump components are matched sets. DO NOT mix old and new parts.

OIL PUMP COMPONENT THICKNESS

Inspect servo pistons and seals for damage or cracks. DO NOT remove seals unless replacement is required. Inspect springs for damaged coils.