Good Morning
I have a 2004 Buick Rainier. AWD 5.3 V-8 115,000 miles on it. I am having a difficult time fixing the AWD

It started with the wheel chatter while making tight turns. My local mechanic diagnosed it as a bad AWD actuator motor on the transfer case. He replaced it with a used one. Problem got better but not eliminated. I changed fluid in both front and rear diffs. This also helped for a short time especially in the front diff. But now it has severe wheel hop in the rear. The hop is always the inside tire when turning tight to the L or R. I changed the entire rear axel. Problem continues. Last thing I did was remove the actuator motor and did a few tight turns in the driveway. Problem went away. My question is... Is this a motor installation problem or is there a problem with the control for the actuator motor? When I install the motor the bolt holes on the motor don't line up with the hole on the transfer case. They are about 1/2 hole off so I have to rotate the motor a little to get the bolts in. Could this be the problem? Is there a proceedure for getting the internal working on the transfer case aligned with the motor?
Any help is greatly appreciated
Thank you
Brian