Another failure on the BMW 3 Series are the factory BMW RTABs (Rear Trailing Arm Bushings), which are made from a very soft material to provide the quietest, most comfortable ride possible. Because of this, factory RTABs do sometimes fail as early as 50,000 miles and 3 years. Bimmerzone provides you with a few brands of aftermarket polyurethane BMW Rear Trailing Arm Bushings that is stiffer and stronger compared to the stock BMW RTABs and thus giving you a longer use of these bushings. Do check out the various popular brands that we carry that includes Powerflex Rear Trailing Arm Bushing (4608), ARD, and Rogue Engineering.