There are several bulletins from GM pertaining to shifting quality and problems. In order to accurately diagnose this problem you should take the car to a reputable transmission shop for a thorough diag. Most will give a free estimate and always ask for an estimate and inquire about parts and labor warranties/guarantees.
#03-07-30-012B: Transaxle or Transmission Slips, Wont Shift, No Reverse, 2nd, 3rd or Overdrive, Erratic Shifts (Replace Driven Sprocket Support Assembly) - (Aug 22, 2005)
|Subject:||Transaxle or Transmission Slips, Won't Shift, No Reverse, 2nd, 3rd or Overdrive, Erratic Shifts (Replace Driven Sprocket Support Assembly)|
|Models:||2002-2003 Chevrolet Cavalier, Malibu|
|2002-2003 Oldsmobile Alero|
|2002-2003 Pontiac Grand Am, Sunfire|
|with 4T40E or 4T45E Transmission|
This bulletin is being revised to update model years, clarify part inspection procedure and warranty return request. Please discard Corporate Bulletin Number 03-07-30-012A (Section 07 -- Transmission/Transaxle).
Some customers may comment that the transaxle/transmission slips, will not shift, will not backup/no reverse, no 2nd, 3rd or overdrive gears and erratic shifts.
A sleeve WITHIN the driven sprocket assembly (401) may have shifted due to insufficient interference fit, blocking the oil feed hole for the second clutch.
- Disassemble the transaxle completely and inspect the driven sprocket support assembly oil feed hole.
Callout "A" shows oil feed holes that are not blocked. Callout "B" shows what the oil feed holes will look like if the sleeve has shifted.
| • ||Inspect the 2nd clutch and other components for possible damage. A major overhaul kit is not required for a Driven Sprocket Support Assembly replacement only.|
| • ||Driven Sprocket Support Assemblies that the oil feed hole is not blocked / sleeve shifted should not be replaced.|
- If the oil feed hole is blocked, even partially, the Driven Sprocket Support Assembly should be replaced. Refer to Driven Sprocket Support Assembly in Unit Repair in SI.
Important: Inspections of returned Driven Sprocket Support Assembly at the Warranty Parts Center (WPC) indicated that the Driven Sprocket Support Assemblies are being replaced unnecessarily. Technicians should carefully inspect the sleeve inside the Driven Sprocket Support Assembly for the correct position before replacement.
- All Driven Sprocket Support Assemblies replaced will be requested for return through the WPC for inspection of sleeves which have turned / shifted.
Driven Sprocket Support Assembly
#02-07-30-013E: Incorrect Transmission Shifts, Poor Engine Performance, Harsh 1-2 Upshifts, Slips 1st and Reverse, Torque Converter Clutch (TCC) Stuck Off/On, DTCs P0757, P0741, P0742, P0730, P0756 - (May 20, 2005)
|Subject:||Incorrect Transmission Shifts, Poor Engine Performance, Harsh 1-2 Upshifts, Slips 1ST and Reverse, Torque Converter Clutch (TCC) Stuck Off/On, DTCs P0730, P0756, P0757, P0741, P0742 (Clean Transaxle Valve Body and Case Oil Passages of Debris)|
|Models:||2001-2005 GM Passenger Cars with 4T65-E Automatic Transmission|
|2001-2005 Buick Rendezvous|
|2001-2004 Chevrolet Venture|
|2001-2004 Oldsmobile Silhouette|
|2001-2005 Pontiac Aztek, Montana|
|with 4T65-E Transmission (RPOs M15, MN3, MN7, M76)|
This bulletin is being revised to include additional diagnostic information and clarify model usage. Please discard Corporate Bulletin Number 02-07-30-013D (Section 07 -- Transmission/Transaxle).
Some owners may comment on any one or more of the following conditions:
| • ||The SES lamp is illuminated.|
| • ||The transmission slips.|
| • ||The transmission does not shift correctly, is very difficult to get the vehicle to start moving or the engine lacks the power to move the vehicle.|
| • ||Poor engine performance.|
The most likely cause of the various conditions may be chips or debris:
| • ||All years--Pressure Reg. Valve (Bore 1) or Torque Signal Valve (Bore 4) stuck.|
| • ||On 2001-2002 vehicles, a plugged orifice on the case side of the spacer plate.|
| • ||ON 2003-2005 vehicles, restricted movement of the 2-3 shift valves in the valve body.|
| • ||On 2003-2005 vehicles, restricted movement of the 3-4 shift valves in the valve body.|
Technician Diagnosis and Correction
| • ||The technician's road test reveals the vehicle launches in third or fourth gear (high RPM with slow vehicle acceleration).|
| • ||On 2001-2002 vehicles, a DTC P0756 or P0757 may be stored.|
| • ||On 2003-2005 vehicles, a DTC P0730, P0741, P0748 or P0757 may be stored.|
| • ||Refer to the appropriate Service Information (SI) for additional Diagnostic Assistance.|
| • ||With a Tech 2® connected to the vehicle, road test the vehicle and perform the following steps:|
If the above symptoms are present proceed with the following steps.
- With the valve body removed and on a workbench, carefully push the valve against spring pressure to check if the valve will snap back to the original position. Or for the valves seated in home position, use a small flat-bladed screwdriver and carefully pry the valve off its seat, quickly remove the screwdriver allowing the valve to return to its seat. If the valve does not snap back unencumbered, then the valve will need to be removed from the valve body.
- Once the valve is removed, inspect for any scratching or scoring.
- If any scratching or scoring is found, then the fingernail test will need to be performed.
Important: It has been found that in most cases that the scratches are not severe enough to catch your fingernail.
- Using your fingernail, move over any scratches to see if your nail will catch on the scratch or score.
|• ||If your nail catches in the scratches, the valve will need to be replaced. |
|• ||If your nail does not catch in the scratches, continue with the next step.|
Important: Clean the valve body with the machined side down so debris may escape.
- Clean the valve and bore using brake cleaner.
- Blow off with shop air.
- To verify free movement of the valve, dip the valve into clean ATF and install the valve back into the appropriate bore. The valve should move freely. If the valve moves freely, in most cases the valve body will function properly when reinstalled.
- Reassemble and retest .
|(1)||Bore 1, Pressure Regulator (Reverse Boost Valve inside bushing)|
|(2)||Bore 2, 1-2 Shift Valve, Solenoid "A"|
|(4)||Bore 4, Torque Signal Valve, Pressure Control Solenoid|
|(5)||Bore 5, Pressure Relief Valve|
|(6)||Bore 6, PWM and TCC Control Valve|
|(7)||Bore 7, TCC Regulator Apply Valve|
|(11)||Bore 11, 3-4 Shift Valve, 4-3 Manual Down Shift Valve|
|(12)||Bore 12, 2-3 Shift Valve, 3-2 Manual Down Shift Valve|
|(14)||Bore 14, Secondary 1-2 Accumulator Valve|
|(15)||Bore 15, 2-3 Accumulator Valve, 3-4 Accumulator Valve|
|(16)||Bore 16, Solenoid "B"|