Driveline vibration or shudder, felt mainly on acceleration, coasting or under engine braking, can be caused, among other things, by improper driveshaft installation or imbalance. If driveshaft vibration is suspected, proceed as follows:
- Raise and safely support the vehicle.
- Remove the rear wheel and tire assemblies and the rear drum or rotor assemblies.
- Mark the position of the driveshaft to the rear axle companion flange.
- Mark one hole position on the driveshaft yoke at the rear of the driveshaft with the letter A and the 8 circular axle flange holes (starting with the mating hole with driveshaft position A) from one through eight. Position A1 is considered the original index position.
- Disconnect the driveshaft from the rear axle flange and re-index 180 degrees at axle position A5. Check for vibration at road test speed. If vibration is still present, evaluate positions A3 and A7.
- If further improvement is desired, evaluate the remaining positions that are located between the best of the 2 previous positions, A3 and A7. If the vehicle tests okay at any point during this procedure, do not proceed further.
- If re-indexing at the axle is unsuccessful, disconnect the driveshaft and re-index 180 degrees at the transmission output shaft only.
- Reconnect the driveshaft and check for vibration at road test speed. If the vehicle tests okay, do not proceed further.
- If re-indexing at both the axle and transmission is unsuccessful, mark the rear of the driveshaft in 4 equal parts and number than 1, 2, 3 and 4. Install a screw-type hose clamp with the screw at position 1.
- Check for vibration at road test speed. Rotate the clamp to each of the other 3 positions and check for vibration.
- If the vibration is worse in all positions, go to Step 15. If the vibration is better in any one position, go to Step 11. If the vibration is better in any two positions, rotate the clamp screw to a mid-point between the two positions.
- Install another clamp, with the screw in the same position as the first clamp. Check for vibration at road test speed.
- If the vibration is acceptable, do not proceed further, the problem is corrected. If the vibration is the same, or worse, go to Step 13.
- Rotate the screws of the clamps equally away from each other about 1 / 2 in. Check for vibration at road test speed.
- If the vibration is acceptable, do not proceed further, the problem is corrected. If the vibration is not acceptable, go to Step 15.
- Install the drum or rotor assemblies and wheel and tire assemblies. Road test the vehicle; vibration felt when the car is raised may be acceptable during a road test.
- If the vibration is acceptable, the problem is corrected. If the vibration is not acceptable, investigate other driveline components: wheels, tires, axle bearings, etc.