Vibration: Could it be improper install of lift kit?

Just purchased a 2006 XTR and I'm having issues with bad vibration while accelerating. The seller told me he added the lift kit and replaced the tires with ones from a 4runner. My first thought was the tires needed rebalancing but that has only helped a small bit. Could the lift kit cause it or am I looking at something else? He also had the u-joint replaced.

 

Welcome

Yes the lift can cause vibes... did you install a carrier bearing drop? What lift and how high?

 

Check the u-joint angles and align per Spicer's recommendations. If you follow their guide, the carrier bearing drop isn't as desirable as matching pinion angle to transfer case output shaft angle.

 

Thanks guys. I really know nothing about what he did or didnt do. I checked and the leaf springs were never replaced so while I have it in the shop Ill have them look at it.
Peace