Hello everyone,

I put in a TW HD front driveshaft and a new vibration occurred @ 70-75MPH. I pulled the driveshaft and sent it back to have it balanced. I threw my original driveshaft in while the TW was getting balanced and I have no vibration, so figured it just needed balanced.

Received my newly balanced shaft from TW and threw it in today. The vibration is back!! I originally thought that maybe it was an output flange (either @ the diff or t-case), but wasn't sure why it wouldn't do that with the other driveshaft?

The TW does weight a lot more than the other one, so maybe that has something to do with it? Any thoughts on what I can test to determine what the problem is?


Thanks everyone!

 

Even though it weighs more, if it's balanced it shouldn't make a difference. If it's good with your old one then that sort of rules out everything else. The TW must still be out of balance.

 

Thanks. According to TW they "triple checked" the balance. Doesn't mean it still isn't balanced, but that would be quite strange. Could the extra weight be putting more stress on the output bearing?

 

I'm not really an expert on that but it sounds logical although I'm not sure how likely. Did you notice any play? Someone else on here will eventually chime in on this I'm sure.

 

I'm watching this thread because a buddy of mine has the identical Disco II I have, identical lift, identical everything and we both ordered HD driveshafts from different places and he has the same problem, down to the original working fine and the new one having been checked and re checked, while I have no vibration at all. So, subscribing. We can't figure it out.

 

Yes, it could still be out of balance.
It could also be a worn output shaft bearing or outer pinion bearing, the extra weight of the TW shaft causing it to make itself known.

I'd give TW a ring and tell them it's still vibrating and see what they say.

 

How much heavier is the new shaft, 20%, 50% or 100%. My guess is it may be 50% heavier which should make little or no difference provided it is correctly balanced and running concentrically, the last point also is important.

How do you know they defo checked or rebalanced the shaft "because they said so" it always depends on their allowable error margins and equipment even if they did re-balance.

There are many factors to consider, how well does it fit on the flanges, is your vibration defo the shaft or maybe it's the t.case output bearing or the diff pinion bearing. Maybe put a dial gauge on these flanges and check them out for movement.

 

While true, my guess would be that Tom Woods has low error margin, good equipment and good people.
They are a major driveshaft shop used by 1000's of very serious off-roaders. They also have a lifetime warranty on their u-joints, which includes any shaft damage due to a failed u-joint, so they certainly have a vested interest in a good product. And an out of balance shaft will wear a u-joint.

 

Take the drive shaft to a professional "Drive Line Shop" They will spin balance it and probably out a different weight or two on it and you are good to go.