The e46 M3 is actually one of the most reliable cars BMW has built in the last 10 years . . . unless you have the SMG option on your transmission of course. The first generation SMG (or Sequential Manual Gearbox) transmissions have not held up well over the long run and are starting to empty the pockets of their loyal owners. So if you are in the market for an e46 M3, stay clear of the SMG. If you currently have an SMG M3, this may be what you’re in for if you haven’t had the pleasure already.