If you've noticed your 1966 Mustang's transmission isn't shifting as cleanly as it once did, then it's time to make a choice. You can fix your existing transmission or replace your 1966 Mustang transmission if that makes more sense to you.

For many classic Mustang owners, keeping the original engine and transmission operating smoothly is part of the fun of owning a first-gen. With high-quality clutch kits, rebuild kits, valve bodies, and other hardware, you can keep your original Mustang transmission running as crisply as it ever did. If you're increasing your engine's power, then you'll want to upgrade your 1966 Ford Mustang transmission to match. For big changes, like Coyote swaps, changing out the transmission is a crucial part of getting the new engine to run well in your '66.