i have original Pirelli p7's. I was hit and the auto body shop replaced one tire at around 22K miles. new tire (LF) center tread depth is 10/32". original RF is 3/32". I believe the max delta is 1/8", which I am over. is this true? could I have differential damage once I go back to these tires? (currently have bridgestone blizzaks for winter package. do I need new tires? believe 3/32" is approaching the risk area. any recommendations for new performance tires? audi is not outfitting their cars with Pirellis anymore, so I hear.