Chassis Reinforcement Kit for E46 REAR | 323 325 328 330 M3If you own a E46 NM or E46 M3 and you are experiencing unfamiliar sounds coming from the rear of your BMW whenever the throttle is being applied, then chances are that your rear subframe sheet metal may already been torn away and is the cause of these noises. The whole rear subframe of the BMW as well as the differential and rear suspension are all secured by bolts threaded into the sheet metal body. It is the splitting and cracking away of the sheet