Joined: Jul 2007
Location: Dallas-Ft Worth
Undoubtedly, your Mustang came with a 2.785, 2.80, or 3.00 rear gear ratio. The next step would be a 3.25, which is about all the ratio I would recommend. When you move up to 3.40 or 3.50 gears, you are turning a lot of RPM's at highway speed, which is annoying.