SuperPro's rear differential mount replaces the soft and fast-wearing OEM rubber mount. The 90A version found here offers significantly reduced deflection under load and more positively locates the rear differential under power application and hard shifts better and more efficiently transmitting power and making for quicker shifts and less interruption in power delivery. The higher durometer material can result in a small amount of additional NVH. We recommend this version over the standard versions for high-horsepower applications and those that see track use (circuit or drag racing).