when i take off from a stop i feel a vibration for about a second and a half then it goes away......its a four link setup and is bagged but i always drive it at the same hieght......its been happening for awhile but doesn't seem to be getting worse..........and its only if i take off a little hard......and its an extended cab........could it be u joints?......was wondering how many things could be causing this .....thanks

 

Sounds like a problem with your pinion angle. Do you have shims under the axel to compensate for the drop?

 

do you need shims with it bagged?........if i raise it to stock hieght it still gets the vibration........does that matter?