Correcting Vibration at the Pinion Nose

Most first-order driveline vibrations originate at the pinion nose end of the drive shaft. Ensure that the vibrations are at a minimum at this location in order to achieve acceptable results. Reduce the runout of the components to a minimum. Balance the driveline as a system when necessary.

1. Measure the runout of the propeller shaft and inspect the tolerance.
2. If the tolerance is excessive, mark the position of the shaft for future reference and rotate the shaft 180 °.
3. Reinstall the shaft and reinspect the runout. Inspect the level of vibration in order to determine if the vibration is lower or corrected.
4. If the runout is still excessive, or if the vibration is still present, measure the pinion flange runout. Replace the pinion flange or re-index the flange 180 ° if the pinion flange runout exceeds the tolerance.
Remove and reinstall the pinion flange only once on axles utilizing a crush type sleeve.
Replace the sleeve with a new sleeve if the sleeve is crushed. Removing the sleeve requires removal of the ring and pinion set. Replace flanges with excessive runout.
Regardless of the method used,measure the pinion flange runout in order to ensure that the flange is within tolerance.
5. Reinspect the propeller shaft runout if the vibration is present after the pinion flange runout is corrected. If the propeller shaft runout is still excessive, correct the runout before doing a driveline system balance. Either replace the shaft with a shaft that is within tolerance or sublet the shaft to a reputable independent for straightening and re-balance. Ensure that the new or rebuilt shaft is within runout tolerance before continuing.
6. Once the propeller shaft and pinion flange are within runout tolerances,inspect to see if the vibration is still present. If the level of the vibration is still unacceptable, perform a driveline system balance procedure.