M/T - High Clutch Pedal & Shift Effort or Gear Clash
90oldsmobile06SUBJECT HIGH CLUTCH PEDAL EFFORT WITH HIGH SHIFT
EFFORT OR GEAR CLASH (PROCEDURE AND NEW PARTS)
MODELS/YEARS 1987 CUTLASS CALAIS, 1988-1989 CUTLASS
SUPREME, 1987-1988 FIRENZA EQUIPPED WITH HM282 5 SPEED TRANSAXLE (RPO-MG2)
NUMBER: 89-T-156
CORP. REF. NO: 937207
DATE: April 1990
SECTION: 7C
Figure 1:
CONDITION: Owners of some of the above vehicles equipped with HM282 5-spd manual transaxles (Figure 1) may comment about high clutch pedal effort accompanied with high shift effort or gear clash.
CAUSE: The above conditions may be due to galling or heavy scoring between the release bearing and input shaft sleeve/bearing assembly. However, any of the following could also be contributing to the condition, therefore; in order to fully determine the cause of the concern each of the following should be inspected.
1. Clutch pedal and associated hydraulic system for binding or loose fasteners.
2. Galling or heavy scoring on the inner diameter of the release bearing or outer sleeve diameter of the input shaft bearing/sleeve assembly.
3. Clutch fork shaft for freedom of movement in its bushings/needle bearings.
4. Clutch fork shaft for misalignment to the release bearing or input shaft bearing/sleeve assembly.
5. Clutch wear.
CORRECTION:
1. Inspect the clutch system linkage external to the clutch housing for binding or looseness and replace or tighten as required.
Figure 3 - Case Disassembly View:
2. Reference Figure 3
Inspect the sliding contact areas between the release bearing and input shaft bearing/sleeve assembly. Also inspect the release bearing pads (fork contact points) for wear or bending. Use solvent to clean the pans.
Figure 2:
If the sliding contact areas are heavily scored, grooved or galled or if the release bearing pads are bent or heavily worn; then the release bearing and input shaft bearing/sleeve assembly should be replaced. A new release bearing with a nylon lined inner diameter (Figure 2) and a new input shaft sleeve/bearing assembly with a different surface finish are available. Installing a new release bearing on a damaged input shaft sleeve/bearing assembly will result in only a temporary repair for the customer.
Removal and replacement of the input shaft bearing/sleeve assembly should be performed per Service Manual Section 7B1 (Unit Subassembly Repair and Inspection) using Kent-Moore service tool J-35824. When pressing the old bearing out and the new one in take special care to ensure that no bearing "cocking" occurs.
Bearing "cocking" may result in bearing pocket damage, clutch housing cracking, or premature bearing wear. If the tool is not available, or there was any damage to the clutch housing while pressing the bearing in or out, a new housing should be used.
3. Make sure the fork shaft rotates freely in its bushings and ensure that it contacts the bearing squarely. Signs of galling or scoring along one side of the sleeve/bearing assembly is a good indicator of misalignment. Also inspect the clutch fork tips for excessive wear.
If the shaft does not rotate freely, has excessive fork tip wear, or misalignment is apparent; then the fork shaft, bushings and seal should be replaced.
4. Inspect the clutch pressure plate and disc assembly for excessive wear based on the vehicles mileage. It is normal to expect pedal efforts to increase with mileage accumulation. However, it is not normal to encounter very high pedal efforts with a slightly worn clutch. This would definitely indicate another problem in the clutch system.
If the clutch assembly does show more wear than normal, it should be replaced. It is also very important to inspect and repair the rest of the system.
IMPORTANT: During reassembly, make sure contact areas (i.e. sleeve, inner diameter of bearing, and fork contact pads on bearing) are cleaned and lubricated with high temperature grease. Excess grease can cause clutch durability concerns.
SERVICE PARTS:
Part Name Part Number
Bearing Assembly, Clutch Release 8672339
Bearing/Sleeve Assembly, Input Shaft 8672128
Kent-Moore bearing removal tool J-35824
Parts are currently available from GMSPO.