Well, I got the bearings replaced and yes, I had to buy another set of bearings and collars as well as two new seals. Probably was not necessary to buy new seals but I just wanted to make sure I had all the parts at hand since I absolutly need my WJ by Tuesday night.
Pat's Driveline in Fort McMurray, Canada are a joke. I phoned them this morning and told them that the bearings for sure are installed incorrectly. He quickly said they installed them according to my instructions. I never gave instruction at all, just ask if they can press the bearings on. I ask them if they can get new bearings and the answer came very quickly with a firm "NO". At first they were going to charge me another C$100 to press them in (minimum 1/2 hour shop rate at C$195/hour...), but finally gave in and told be to bring in the bearings.
I still have a humming sound coming from the rear of my car and I am afraid it is the diff. It starts at around 30mph but is not very loud at all. I got Castrol 80/90 gear lube in it. Would full synthetic oil be better for my diff? I kn ow it is not a fix but will it prolong the life of the diff?