Post lift drive-line vibration

Hey fellas. I recently lifted my 02 extended cab with allpro coil overs, upper a-arms, and their full leafs. I started to experience a drive line vibration from around 55-70 MPH. it has the front diff drop kit. Its somewhat throttle sensitive, but not gear sensitive, so it leads me to believe its possibly rear drive shaft angle. has anyone else had this problem and knows a way to alleviate it? possibly a leaf angle shim kit?

thanks!

 

How many miles? How are ujoints and carrier bearing? Don't just say good either. Test carrier. When did you last grease ujoints?



At 4 inches of lift I have zero vibe on the rear with new drive line and carrier bearing.

Some do a carrier bearing drop.

 

truck hads 110,000, and vibration started immedatly after the lift. i grease the joints every 3000 miles.
just checked the carrier bearing and u-joints, no play at all. Ill drop the carrier bearing and see what happens. thanks!

 

update: performed carrier bearing drop, and its damn near perfect for rear drive line angle, with no change in vibration. this leads me to believe that the vibration may be coming from the front C/V axles, however, I installed a front diff drop. is there any other known common causes? or will i have to scale down the adjustables a bit.