No this isn't quite "normal" as people make it out to be. Improper driveline maintenance and/or driving skills are to blame. A "normal M clunk" is almost nothing and only shows up quietly when you improperly shift. A well maintained driveline will be very solid and free of issues. This includes; motor mounts, transmission mounts, center support bearing, center support, giubo, differential bushings, differential bolts (which break), differential condition, subframe bushings, subframe pan, rear trailing arm bushings and ball joints. If you've owned a low mileage well cared for car you know what the E46 M3 is supposed to feel like. If you haven't and you have a 60k+ car, I suggest you start turning some wrenches to inspect each and every failure point.
Last edited by braymond141; 09-30-2012 at 04:05 PM.