Even though the M range is the pinnacle of the brand, recalls can happen. This time the problem is due to dodgy bolts.
This BMW M-car recall is something a little different. What we understand from the bulletin issued by the NHTSA is that this recall comes as a result of a previously issued recall, but affecting a different component. A while back there was a recall on certain M-cars that necessitated a change to the slip joint in the driveshaft that somehow left the factory minus grease which could result in it ceasing up and possibly causing an accident. That change resulted in this recall thanks to reused bolts.
The NHTSA tells us that during servicing of the rear differential for a prior service action (the recall mentioned above), the rear sub-frame bolts may have been reused instead of being replaced. Re-use of the existing bolts may cause the bolts to loosen. This means they're a stretch bolt of some kind, like a cylinder head bolt. As you can imagine, bolts coming loose on a car is never a good thing, and on a high-performance car it's especially bad. The NHTSA goes on to say that loose rear sub-frame bolts may adversely affect vehicle's handling and control, which, as expected, can increase the risk of a crash, depending on what the car is doing when things come loose.
BMW will notify owners of the affected cars and dealers will replace the rear sub-frame bolts with new bolts, free of charge. The recall is expected to start on October 24, 2016. Some owners of 2016 BMW M2 coupes, 2015-2017 M3 sedans and 2015-2016 M4 models in both coupe convertible models will be affected. We're hoping M-car owners will be a little more in tune with their cars and would identify a knock or something not right before being contacted by BMW.