Brothers Performance offers performance manual transmissions from Ford Racing and Tremec. Tremec heavy duty 2005-10 Mustang manual transmissions are designed for high horsepower applications. If you are making 400 plus horsepower, chances are you will need to upgrade your 2005-10 Mustang’s manual transmission before you leave it in pieces on the highway or race track. Take a look at the Tremec TKO 500 or 600 race series Mustang manual transmissions.