Trans has been flushed twice (not recently). Sometimes "bangs in" sometimes "slushes in".
I'm a retired GM Mech Engineer with design/performance background in roller clutches an trans bearings, just been "out-of-loop" for 10 years.
Great answer - hope your correct! I'll try those remedies, and check the "codes" also (have my own diagnostics).
Please answer "What problems have you seen / not seen in high mileage roller clutches?? Just curious, but would like to contribute expert opinions when requested.
Please e-mail me (it's pro-bono) for any really technical clutch or bearing issues.
Soon as you respond, I'll pay-up.
Please e-mail me XXXXX@XXXXXX.XXX (it's pro-bono) for any really technical clutch or bearing issues.
Bulletin No.: 06-07-30-023C
Date: October 15, 2009
Subject: 4T65E Transmission 1-2 Shift Shudder at Light to Moderate Acceleration (Replace Complete Second clutch Assembly)
Some customers may comment on a 1-2 shift shudder at light to moderate acceleration. Typically, the throttle plate angle parameter is 12-20% at time of condition with vehicle speed of approximately 24-40 km/h (15-25 mph). The customer may describe the condition as slip or delayed shift into second.
Replace the complete second clutch assembly with service kit, P/N 24240561. Refer to the GM Unit Repair Service Manual for the year and model of the vehicle being serviced for the 2nd Clutch service procedure.
This service kit contains: Second Clutch Housing Fluid Seal Rings (613), a Second Clutch Assembly (617), a Case Cover (Channel Plate) Upper Gasket (430), and a Case Cover (Channel Plate) Lower Gasket (429). In addition to the content of this service kit, other gaskets not included in this service kit will also be needed to complete the repair - a Case Cover Lower Gasket (429), and a Case Cover Upper Gasket (430). These gaskets can be obtained by ordering gasket kit 24206391.
Be sure to use ONLY the Second Clutch Assembly and Second Clutch Housing Fluid Seal Rings provided in this service kit. DISCARD the Second Clutch Assembly and Second Clutch Housing Fluid Seal Rings removed from the transmission being serviced.
Disassemble ONLY the Oil Pump Assembly from the Case Cover (Complete). DO NOT disassemble the Control Valve Body from the Case Cover. Remove ONLY the Case Cover-to-Case bolts to remove the Case Cover and Valve Body from Transmission Case AS AN ASSEMBLY . To access all Case Cover-to-Case bolts, it is necessary to remove the Pressure Control Solenoid Valve Assembly (322), and 1-2 & 3-4 Shift Solenoid Valve Assemblies (315A, 315B).
Bulletin No.: 08-07-30-002A
Date: March 12, 2008
This bulletin is being updated to include Related Service Document information. Please discard Corporate Bulletin Number 08-07-30-002 (Section 07 - Transmission/Transaxle).
The following new service information will aid technicians in providing easy to follow valve body reconditioning instructions and new illustrations to simplify reassembly of the valve body.
Related Service Document
Corporate Bulletin Number 02-07-30-013 : 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.
Left Side Control Valve Body Assembly
Right Side Control Valve Body Assembly
1997-2000 M.Y. Only - Right Side Control Valve Body Assembly
Valve Body Spring and Bore Plug Chart (Metric)
Bulletin No.: 02-07-30-039F
Date: July 27, 2005
with 4T65E Transaxle (RPOs MN3, MN7, M15, M76), 4T40E/4T45E Transaxle (RPOs MN4 or MN5) or 4T80E Transaxle (RPO MH1)
with PWM Solenoid Manufacturing Julian Dates Between 219 and 3048
This bulletin is being revised to change the statement of Transmission Release Pressure to Torque Convertor Clutch (TCC) Release Pressure. Please discard Corporate Bulletin Number 02-07-30-039E (Section 07-Transmission/Transaxle).
Some customers may comment that the transmission shifts hard, a shudder/chuggle is felt on deceleration or the Service Engine Soon (SES) light is illuminated.
A technician may find DTC P0742 set.
Customers with 4T80E transaxles may also comment on a "bump" feeling at approximately 61-68 km/h (38-42 mph) when they lift and then tip into the throttle. There may also be a concern of whine noise in 3rd or 4th gear with or without the Service Engine Soon light/message displayed and with DTC P0742 set.
DO NOT REPLACE THE VALVE BODY AND PUMP ASSEMBLY.
Perform one of the following diagnostics:
Replace the TCC PWM solenoid using published procedures for the vehicle being serviced.