This is very good food for thought. I will not just up and replace the diff yet. Mechanic emphasized how hard these issues were to track down.

I had a bad U joint once on a BMW 635 and changed driveshaft out myself as it wasn't serviceable. But in that case it was an rumble not a gear grind as the u joint was getting stuck and the driveshaft was destroying the center bearing. I don't think its the u joint. But who knows its a totally different car.


Ergh .

Henry