The differential mounting bolt will fail causing your differential to fall which breaks your driveshaft your transfer case and your exhaust system. This has been reported in well over 100 cars there is no warning light if driving at interstate speeds and this happens it could be catastrophic.

- Kansasville, WI, USA

Was driving the vehicle home and while driving I heard a loud pop and a thump. Had the vehicle towed home to see that the real differential bolt had sheared off the head!

- Dayton, OH, USA

The differential is making clicking noises at low speed especially when on and off the gas.

- East Lansing, MI, USA

Rear differential disconnected from vehicle due to mounting bolt snapping, rear differential was also previously replaced by bmw before I purchased vehicles due to rear differential failure

- Newark , DE, USA

The rear differential bolt is a known failure point on these cars. I see it time and time again where there is a clunk noise coming from the rear of the car and sure enough, the bolt has broken on the rear differential and leaves the car undriveable. BMW has said that they are unable to do anything without NHTSA informing them of the issue. There needs to be a recall or active service bulletin to address this issue. This failure is not a matter of -??if-??, it is a matter of -??when-??. There needs to be a stronger bolt in place otherwise it is a near $5000 repair to replace the rear differential if not covered under warranty.

- Chalfont, PA, USA

Consistently breaking differential bolt that hold the rear differential in place, very widespread issue as well as being consistently noted in forums. Also a high number of differential completely failing across all years. Mine failed recently, two other vehicles at the same dealership had a broken differential. There needs to be a recall on both of these issues.

- Louisville, KY, USA

The issue is with the rear differential carrier bolt, Part # 33176760336. This bolt shears at the hex head and causes the differential assembly to misalign with the rest of the driveline components and causes further failures of the driveshaft and other items. Just in the past month I have seen several people post on the BMW X3M facebook groups and also on Internet forums about their broken bolt causing issues. The OEM bolt is a 10.9 grade bolt that does not appear to be able to take the stress put on it for daily driving. My car is exhibiting symptoms that others have heard in their cars before the failure occurred, Clunking when putting the car into drive or reverse. This can also be heard while going into second gear and driving at 5-20mph on light throttle then letting off the gas pedal and getting back on, this will cause the differential to clunk back onto the bolt and off. This is a failure due to a simple bolt component that could be enhanced by BMW to a higher tensile strength to avoid this situation from happening on the highway.

- Flanders, NJ, USA

Vehicle engine RPM will arbitrarily increase from 500-600 RPM to 1200-1500 RPM while idling in drive and at operating temperature, such as at a stoplight or in a drive-through. The vehicle also makes a distinct clunking sound under normal stop-and-go driving conditions.

- Glendale, AZ, USA