C3.....Driveline vibration

[Mike M.]

Re: C3.....Driveline vibration

One other item that could cause the problem but really not be evident. Most drive shafts have weights spotwelded to them for balancing. I have seen the welds fail and the weight get thrown off. Instant driveshaft imbalance. If every thing else checks out (Duke's list), closely examine the driveshaft to check for a loss of a balance weight (i.e., spot weld mark with nothing attached). Or take the driveshaft to a shop and have it checked for balance.
Mike

[Terry M.]

Re: C3.....Driveline vibration

Also consider the possibility that the driveshaft may be bent. A straight tool, like a level can easily check for straightness.

[John Walker]

Re: C3.....Driveline vibration

One other thing to think about here is, u-joints, when you have the car up in the air, check each u-joint with your fingers, put your thumb and index finger on the joint caps (where the seals are), then take the driveshaft in your other hand and push/pull the shaft from side to side and then up and down, rotate the drive shaft 180 degrees and feel again. Sometimes it won't take much movement on the joint to cause a driveline vibration. this vibration is slower than the vibes from a bent shaft or missing weight. A practiced "butt" or even better feet or hands on the steering wheel/ door jamb or other solid object will be able to discern d/s or u-joint most of the time. If the vibe starts out slow and increases with "ROAD" speed it is drive shaft related.

[Doug Flaten]

Re: C3.....Driveline vibration

Another thing you might check are your pilot bushings and the tail housing slip yoke bushing that the drive shaft slips into the tranny.