Customer:"Hello? I'd like to buy an axleshaft for my Ford 9-inch rear axle." Salesperson:"No problem. Do you know what length, spline count, and wheel-bolt pattern you need?" Customer:"I really don't.

There's no doubt that one of the most popular and most hyped rearends is the Ford 9-inch. As bulletproof as they come, it's become the go-to rear when it comes to a high-horsepower application, be it ...

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 ...