The Ford 8.8- and 9-inch rear differentials are two of the most popular and best performing differentials on the market.
While the 8.8-inch differential is commonly used in late-model Mustangs, the 9-inch is the most popular and arguably the most dominant high-performance differential for muscle cars, hot rods, custom vehicles and race cars. Built from 1957-1986, the 9-inch Ford differential is used in a huge range
of high-performance Ford and non-Ford vehicles because of its rugged construction, easy-to-setup design, and large aftermarket support.