That is a tough one. There are a few things that can cause the pull, but the differential is a different issue. I need you to check 4 different parts on the vehicle. On the rear axle, there is what is called a suspension bar. There are two, one in each side. See pic 1 (highlighted). Make sure nothing is broken, rusted, the rubber mounts are in good condition and look for anything that stands out. If you see something, take a pic and upload it for me to see. I highlighted the parts I'm referring to. However, I didn't highlight the upper suspension arm (number 2 in the pic). Check it as well.
Next, on the front there are tracking arms. See pic 2 (highlighted). Do the same with them. It isn't uncommon for the bushings to go bad and egg shape the steel arms.
Do this and let me know what you find.
Images (Click to enlarge)
Thursday, February 13th, 2020 AT 8:28 PM