I had a diff explode on my last 164Q... happened post accident I was taking it for one last drive, very spirited last drive, and during a hard pull in 1st gear the diff exploded causing the car to not move in any gear. I plan on buying a Q2 diff for the current 164 mostly to avoid the problems the gear set pins have on the stock diffs. Its a lot of money for one but I feel its worth it because replacing a transmission will be a lot more. if one does blow is it possible to get a new diff cover and install a new diff? or does it depend on the extent of the damage?