Went out in the car tonight to see if replacing the ECT sensor had cured the over fueling issue I had on Monday night and it's fine now but when driving it came on boost quit hard and I hit a bump in the road and then heard a bang from the rear and lost all drive

Got the car home and jacked it up to see the prop turning but no driver to the rear wheels so I'm guessing that would be the diff gone.

It was on a standard diff but it seems like a good time to upgrade but just wanted some advice on what other people are using and would recommend?