I experienced the same issue earlier this week. A bolt sheared and twisted the diff. On the way to the dealership, the loose parts opened the rear left break line and I lost brakes (almost crashed). I made it to the dealership pumping the break pedal and using the hand brake. The dealer told me that they won't cover it because I have the Akra slip-on and that's what caused the shear in the bolt. This exhaust's weight is roughly half of the stock exhaust... I did not expect that kind of treatment from BMW.
2011 M3 Coupe; Brilliant White/Amarone; Competition, Tech, Premium Packages; Everything Else...