Posted by RP on August 16, 2002 at 20:35:35:
In Reply to: Drive Line Vibration posted by Yale on :
Yale, the correlation between the times when the vibration occurs and which gear you are in is not the issue. A drive line vibration will happen at a specific road speed or range. You should be able to test this by getting up to the speed at which the vibration happens and then selecting another gear and maintaining the same road speed. If you still get the vibration then we are taking about a driveline imbalance of some sort. If this is the case then the Yellow pages in your area probably have some entries in the category of Driveshafts. Pick one which works with larger vehicles - trucks specifically. Have them dynamically balance yours, (yes you have to take it out for that to happen). It could have been damaged, could have thrown a balancing plate, or was out of balance from the start. Once you have a validated balanced drive shaft and you still have the vibration then you can start looking for more exotic causes, U-joints at incipient failure, worn pinion bearing etc.