bad vibs

[rasyman78]

I had to take my 05 renny in to the dealer for a bad vibration, I just bought it.
So they changed out the front drive shaft since there was a bad joint at the transfer case . I got it back and all seems well until i went to work and at highway speed when i let off the gas i get a bit of vibration and thumping but it don't do it while accelerating . So its back at the dealer and being looked at .
I don't think the mechanic knows what he is doing and all he can tell me is "all I hear is the tires, Man those thing are loud " ( cooper STT's ). so any help would be appreciated . I'm starting to regret buying this jeep but yet i love it p:

 

[DocHemi]

I had to take my 05 renny in to the dealer for a bad vibration, I just bought it.
So they changed out the front drive shaft since there was a bad joint at the transfer case . I got it back and all seems well until i went to work and at highway speed when i let off the gas i get a bit of vibration and thumping but it don't do it while accelerating . So its back at the dealer and being looked at .
I don't think the mechanic knows what he is doing and all he can tell me is "all I hear is the tires, Man those thing are loud " ( cooper STT's ). so any help would be appreciated . I'm starting to regret buying this jeep but yet i love it p:

Front wheel bearings possibly

 

[tommudd]

First how many miles,
lifted or not,
have they checked the rear tri link and rear LCAs
also the rear u-joints and no you can't just grab them to see if they are loose
Are the tires cupped any