Posted on 5/30/2025
The BMW S54, S65, and S85 engines are known for their high-revving performance and motorsport-inspired engineering. Found in iconic models like the E46 M3, E90/E92 M3, and the E60 M5, these engines are among the most exciting ever produced by BMW. However, they also share a common weakness that every enthusiast and owner should know about: rod bearing failure. If you own a car with one of these engines, rod bearing replacement isn’t just a recommendation—it’s considered essential preventive maintenance. Ignoring it can result in catastrophic engine damage and one very expensive repair bill. What Do Rod Bearings Do in the Engine Rod bearings sit between the crankshaft and the connecting rods. Their job is to provide a low-friction surface that allows the rods to rotate smoothly around the crankshaft as the pistons move up and down. These bearings are constantly subjected to extreme forces, especially in high-performance engines that rev well past ... read more