C 3500 Truck 2WD V8-6.6L DSL Turbo VIN 1 (2002)
Accumulator: Customer Interest
A/T - SES Lamp ON/DTC's Set/Slipping/Delayed Shifts
File In Section: 07 - Transmission/Transaxle
Bulletin No.: 03-07-30-005
Date: February, 2003
TECHNICAL
Subject:
Service Engine Soon Indicator Illuminated, Transmission Slips, Engine Flare, Delayed 2-3 Shift, Shifts Missing, No Shift, DTCs P0730, P0756, P0757
(Replace Accumulator Assembly/Service Transmission, If Necessary)
Models:
2002 Chevrolet Avalanche, Express, Silverado, Suburban
2002 GMC Savana, Sierra, Yukon XL
with 4L80E (MT1) or 4L85E (MN8) Automatic Transmission
Built Between February 1, 2002 and April 10, 2002
Condition
Some customers may comment that the Service Engine Soon Indicator is illuminated, the transmission slips, the 2-3 shift takes too long, or the
transmission does not shift properly.
Cause
The condition may be due to an improper finish to the bore of the 2-3 accumulator housing, causing damage to the seals.
Correction
Important:
Verify the vehicle build date in GMVIS. If the vehicle build date is between February 1, 2002 and April 10, 2002, proceed with this bulletin. If not
within the build date, refer to SI for diagnostic procedures.
1.
Road test the vehicle with the transmission fluid and engine coolant temperature stabilized at normal operating temperature. Confirm with the Tech
2(R) that there is a delayed 2-3 shift (greater than 0.45 seconds), or no 3rd gear operation.
Important:
INSPECTION OF A TRANSMISSION FOR EVIDENCE OF CLUTCH MATERIAL OR FINE METAL DEBRIS IN THE PAN DOES NOT A
DIAGNOSIS MAKE. The transmission will have non-magnetic metal in the sediment in the transmission pan. The manufacturing/machining process
of the transmission case creates a very fine aluminum dust, which when combined with the cooling/lubricating fluid turns to a paste. Even though
attempts are made to remove this completely, some will ultimately be missed and will end up in the transmission fluid reservoir (pan). This paste will
always remain in the pan. It can not be picked up and pulled through the filter and affect the operation of the transmission.
2.
Remove the transmission pan and inspect the fluid.
^
If the fluid is in good condition, go to Step 3.
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If the fluid is burned, go to Step 6.
^
If there is metallic debris attached to the magnet in the pan, go to Step 6.
3.
If the fluid is in good condition, remove the accumulator housing assembly and discard the assembly. Refer to SI Document ID # 749332 for the
procedure to remove. Assemble the new 3/4 accumulator assembly and reinstall the components.
^
3rd and 4th clutch accumulator housing is P/N 8684220.
^
3rd clutch accumulator piston seal is P/N 8661647.
^
3rd clutch accumulator piston is P/N 8683088.
^
3rd clutch accumulator piston inner seal is P/N 8661639.
4.
After completing the repair, properly fill the transmission with DEXRON III(R) Transmission fluid.
