Unfortunately, the S54 engine used in early 2001-2003 E46 M3 and MZ3/4 cars was released with a rod bearing failure problem. The factory addressed the issue with a rod replacement, but there is still room on the table for a better bearing solution.
Our treated rod bearings are not coated – coatings too often add too much material and interfere with proper tolerances, causing more problems than they solve. The bearings we use in our kits have been treated with a process that smoothest the grain structure in the surface of the bearing. The treated surface also aids in oil retention, providing more lubricity in this critical area of the S54 engine.