034Motorsport Street Density Motor Mounts for the C7/C7.5 Audi S6/S7/RS7 and D4 A8/S8 with the 4.0T are a performance upgrade over the factory mount. Street Density Motor Mounts are manufactured with 55 durometer rubber to limit unwanted noise and vibration transfer into the cabin. Street Density Motor Mounts are also optimized void-free and fluid-free, eliminating the slop, excess movement, and premature failure associated with the factory mounts, resulting in improved shifting feel and driving dynamics while greatly improving long term durability and longevity. While factory motor mounts will wear and tear prematurely, 034Motorsport Street Density Motor Mounts are reliable for stock and upgraded power levels. Note: While no visible error codes or check engine light (CEL) will be shown on the dashboard, it is possible that some vehicles may have a "soft code" when scanned. There is no cause for concern with this code, as your car will function without issue.