For over half a century, the Ford 9-inch rearend has been the king of aftermarket axle upgrades. Few other axles enjoy the same amount of bolt-on and custom componentry. The Ford 9-inch is a great ...

Pitching the stock differential out from under a GM car in favor of a 9-inch Ford has always been the best way to step up the drivetrain for drag racing. Since the price of used 12-bolts has ...

The Chevy 12-bolt axle shaft (left) is tapered; the Ford 9-inch shaft is the same diameter throughout its length, except for the short section just after the spline end. This makes it easy to narrow ...

Sooner or later, it boils down to what direction you're going to go when your Mustang's rear axle wears out. Some decisions are straightforward. If you have a six-cylinder Mustang, stick with the ...