I had to have the differential rebuilt on my Burb. Apparently it's very common on GM light trucks. I had mine done at a local garage that does really professional work with high end parts, so it was expensive IMO but, it should be good to go for 100,000 miles. It cost me $1,400.00 but, everything was replaced including the half axles.
As to the ghost.. I wish I had a suggestion. I can't imagine what would reset the computer like that. Maybe there's something overheating and cutting the circuit till it cools down. That would be a big deal for me. I can't know that I will be broken down on the side of the road. Wonder if there's a grounding issue..?