My DANA 30 gears burned up from oil changer poor service. I got a differnet entire unit from another cherokee but a different year. It has the same gear ratio but it gets hotttttttt and does not seem to ride well dow n the road. I replaced all bearings, axles, and now a new drive shaft but it still gets up to 270 degrees on the highway. Anyone have any ideas? Not sure of the year I took the diff from but think it was between 93 and 96.
Thanks
'Jim

Gears aren't something you can just pull off one vehicle and install in another, they must be set up using precision tools to ensure the gears are meshing correctly and there's proper bearing preload.

Here's a tech article that explains it all better then I can.

Hope this helps,
Mark