BMW M Car Services

BMW M Car Servicing

(Rod bearings for bmw m models  – e46 m3 , e90/91/92 m3 , e39 m5 , e60 m5, f10 m5
Throttle actuators for M models)

The crankshaft and connecting rods in a BMW engine rotate on thin metal rings known as bearing shells. Over time, these shells wear down and need to be replaced, much like other components subject to regular wear. Ideally, the bearings wear out instead of the crankshaft itself.

When they do reach the end of their service life, they can typically be swapped out for new ones. BMW has never officially specified a replacement interval or expected lifespan for these bearing shells. In our experience, some bearings show significant wear in under 50,000 miles, while others remain in good condition even after 100,000 miles.

What may seem like “premature” wear could actually be normal, or it could point to other underlying issues. The most reliable way to assess bearing wear is to physically inspect them by removing at least one. This process is not as difficult or technical as it might sound, especially if the oil pan is already off. While used oil analysis can provide early warning signs of bearing wear, it’s not as conclusive as a direct inspection. Rod bearings can be replaced on their own, whereas main bearings cannot be replaced independently of the others.