Silverado 3500 2WD V8-6.6L DSL Turbo VIN 2 (2004)
Band Apply Servo: All Technical Service Bulletins
A/T - 4L60-E/-4L65E No Shift/Slipping/Fluid Leaks
Bulletin No.: 04-07-30-025A
Date: July 27, 2004
TECHNICAL
Subject:
Transmission Fluid Leak, Inoperative 2nd/3rd/4th Gears, No Movement, Case Cracked or Broken at 2-4 Servo (Repair Transmission and Install New
Retaining Ring)
Models:
2004 Chevrolet Corvette
2004 Pontiac GTO
2004 Light Duty Trucks
with 4L60-E and 4L65-E Automatic Transmission (RPOs M30 or M32)
Supercede:
This bulletin is being revised to add the Corvette and GTO models and to include the 4L65-E transmission. Please discard Corporate Bulletin Number
04-07-30-025 (Section 07 - Transmission/Transaxle).
Condition
Some customers may comment on a transmission leak, inoperative 2nd/4th gear, slipping 3rd/4th gear or no movement due to excess fluid loss.
Cause
This condition normally occurs at low mileage, usually under 1,600 km (1,000 mi), and investigation may show that the servo cover is loose or that the
transmission case is cracked or broken at the servo bore.
This condition may be caused by a servo cover retaining ring that did not retain the servo cover.
The servo retaining ring design was changed for the 2004 MY from round wire to wire with two flat faces.
In mid-April, 2004, the retaining ring design did revert back to a round design in production.
It is possible that the transmission case may crack at the servo cover area due to the retaining ring being incorrectly seated.
Correction
Important:
^
In mid-April, 2004, the retaining ring design did revert back to a round design in production.
^
If the transmission fluid level has lowered due to loss of fluid, it is possible that damaged 3/4 clutches will result.
^
A cracked or broken case may usually be repaired at a significantly lower cost than transmission assembly replacement by replacing the
case and any damaged clutches or bands.
1.
Raise and suitably support the vehicle.
2.
Inspect the transmission case around the servo cover for signs of cracks or damage to the case.
^
If the transmission case is cracked or damaged, replace the transmission case. Refer to the appropriate SI Document for Transmission Case
Replacement.
^
If the servo cover is leaking and the case is not damaged, continue with the next step.
3.
Remove the front exhaust pipe assembly. Refer to the appropriate SI Document.
4.
Remove the heat shield if equipped. Refer to the appropriate SI Document.
5.
Clean the servo cover area with Brake Clean and shop air.
