I upgraded my zj limited to bigger gears(front and back) and added limited slip to front end.

Mechanic did great job but didn't put abrasive additive into front diff and it pulled left and right.

Once we added it worked great!

PS: Most garages, JLube & EZ don't know about required additive and dont put it in. Most likely a mechanic drained and refilled diff without additive in back diff. Get kit which is like radiator test tube and test additive level or presume it contains none and ADD some until corrected...

Coach James