Wheel hop..
Think you need better control arms, upper and lower,
with poly bushings after your gearchange. The 4.10 or higher gears seems to give more wheel hop problems.
..and, It could bee that your control arms and bushings are binding after the installation. Have you tried to put a couple of friends in the rear seat, and shake them well at low speed in a bumpy road.. If the bolts are tighten hard
in a raised position, this could happends..