I have a feeling this is going to get expensive.

[Ron Sebastian]

So far I have changed tires and had them road force balanced with weight hammered onto the rims, not the little stickers ($1100). Went through two sets of tires, so thinking they are good but the rims are suspect. Then changed all steering tie rods and ball joints ($1200). Just finished adding pinion shims to the rear, now TC and rear end is within specs, also changed out the U joints on the rear drive shaft ($150). Still have a little vibration. Next step is aluminum milled rims and putting my tires on them ($1400), then getting the driveshaft balanced and probably lengthend an 1" or so ($350). I'll get my money back when I sell it right, it's an investment!

 

[85K304SPD]

What is the problem you are trying to fix? What is your set up? From the picture, there is no problem there, although they do look expensive.

 

[WP29P4A]

A mystery vibration?

Has anything you have done so far made any difference?

Two other things to check just to eliminate potential causes would be shocks? Hub centric VS Lug Centric wheels with correct lug nuts? Pretty sure a tire/wheel shop would have noticed Lug centric wheels with the wrong lug nuts, but it sucks when something so small is over looked until after spending a bunch of money.

 

[Camar068]

So far I have changed tires and had them road force balanced with weight hammered onto the rims, not the little stickers ($1100). Went through two sets of tires, so thinking they are good but the rims are suspect. Then changed all steering tie rods and ball joints ($1200). Just finished adding pinion shims to the rear, now TC and rear end is within specs, also changed out the U joints on the rear drive shaft ($150). Still have a little vibration. Next step is aluminum milled rims and putting my tires on them ($1400), then getting the driveshaft balanced and probably lengthend an 1" or so ($350). I'll get my money back when I sell it right, it's an investment!

sorry but I can't imagine spending that much money for anything you've listed.

 

[Matt69olds]

Try flipping the driveshaft 180 degrees in the rear yoke. You could also try reclocking the converter on the flywheel.

 

[ali_c20]

Is the driveshaft in phase ?
There's a great video in this thread
https://www.gmsquarebody.com/threads/do-u-joints-have-to-align-in-any-way.36370/

 

[Ron Sebastian]

Is the driveshaft in phase ?
There's a great video in this thread
https://www.gmsquarebody.com/threads/do-u-joints-have-to-align-in-any-way.36370/

I have seen this video, thanks. That is why I installed the pinion shims to get the angles right. I will try to flip the driveshaft/yoke and see what that does.

 

[Ron Sebastian]

sorry but I can't imagine spending that much money for anything you've listed.

I try not to imagine it too much either!

 

[Big Chip]

Is it a cyclical vibration or constant?

 

[Ron Sebastian]

It starts around 35 mph up to about 55.

 

[Ron Sebastian]

A mystery vibration?

Has anything you have done so far made any difference?

Two other things to check just to eliminate potential causes would be shocks? Hub centric VS Lug Centric wheels with correct lug nuts? Pretty sure a tire/wheel shop would have noticed Lug centric wheels with the wrong lug nuts, but it sucks when something so small is over looked until after spending a bunch of money.

The 4 degree pinion shims corrected the drive line angle and torqued down right. Also traction bars added for anti axle wrap fixed it.