What is the pinion / driveshaft angle relationship look like with the the vehicle setting on the ground at rest?
Pinion angle should be pointing ideally slightly below the driveshaft angle.
As power is applied, the pinion angle tries to rise above the driveshafts straight line angle.
If the pinion angle rises above the driveshaft angle to much, weird vibrations can occur.
What you want is when power is applied is for the pinion angle to stay slightly below or at least in line with the driveshaft angle.
So, a slightly negative pinion angle pointing below the driveshaft angle at full rest is ideal.
If your still running the OEM boomerang, the soft rubber bushings on the body end have a lot of give in them which can contribute to the problem.
The IronRock rear upper control arm bushings are very hard, so they don't allow hardly any give when power is applied to the drive train.
I hope this is not too confusing?
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Supporting Vendor and Moderator of LOST05 Jeep Liberty CRD Limited
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