Subject: | Clutch Noisy, Slipping or Inoperative (Replace Clutch Release Bearing) |
Models: | 1990-2000 Chevrolet and GMC C6-7 Conventional Medium Duty Trucks |
1993-2000 Chevrolet and GMC B7 School Buses |
with Gas or Diesel Engine and Spicer 310 mm Clutch (RPO MRJ), Valeo 13 Inch Clutch (RPO MPJ), or Midland Lipe Clutch |
Built Prior to May 24, 2000 and the following VIN Breakpoints: |
Make | VIN Breakpoint |
---|---|
Chevrolet | YJ523748 |
GMC | YJ523698 |
Some drivers may comment on any of the following conditions:
• | Noisy release bearing |
• | Slipping clutch |
• | Inoperative clutch |
An inoperative clutch release (throwout) bearing may cause this condition. Lack of regularly scheduled clutch adjustments may be the most common contributing factor to an inoperative clutch release bearing.
As the clutch wears, free play in the linkage diminishes. When the clutch is worn to the point where there is no free play, the release bearing will be running constantly. The release bearing was not designed for this abuse and may become noisy. As the clutch continues to wear further, the release bearing will start to push on the clutch fingers and not allow a complete engagement of the clutch. At this point, the clutch will start to slip and may become inoperative in a short period of time.
Reinforce to the customer about strictly following the recommended maintenance schedule for periodic clutch adjustments.
A new clutch release bearing, P/N 15763548 is now available for production and service. This new bearing is more robust and provides the following new features:
• | Full-time running capability with self-centering feature |
• | Lubricated bearing with high-temperature Viton seals |
• | Fully compatible with current and past mechanical clutch apply systems |
• | Inner race rotation for lower bearing speeds |
• | Lubricant-impregnated nylon bushing reduces housing lubrication requirements for life |
Replace the former clutch release bearing with a new bearing, P/N 15763548, on affected vehicles. Refer to the Clutch subsection of the applicable Service Manual for release bearing information and procedures.
It has been common practice to replace a clutch release bearing when installing a new clutch. This may not be necessary with the new P/N 15763548 release bearing.
Part Number | Former Part Number | Description |
---|---|---|
15763548 | 15556905 | Bearing Asm - Clutch Release |
Parts are currently available from GMSPO.
For vehicles repaired under warranty, use:
Labor Operation | Description | Labor Time |
---|---|---|
K0700 | Bearing, Clutch Release - Replace | Use published labor operation time |