Installing Steeda’s S550 Differential Bushing Insert System

Rubber bushings are squishy. They do a great job absorbing annoying vibrations, but they also allow things to move around under load. Sometimes too much for our liking. When we drive our Mustangs aggressively, the rubber bushings in the drivetrain “wind up” under load and then release that energy when the tires break traction. When this cycles back and forth between traction and slip, drivers describe this as “wheel hop.”

Aftermarket companies that cater to enthusiasts like us know that we care less about reducing vibration and more about putting the power to the ground quickly and smoothly. That’s where Steeda Autosports comes in. Their latest offering to stiffen up the connection between the differential and the rear suspension for S550-chassis Mustangs is their Steeda Mustang Differential Bushing Insert System.

Steeda’s ingenious solution doesn’t replace the factory rubber bushings, but rather surrounds the factory rubber bushings with harder polyurethane inserts. The result is a differential that’s more firmly supported without any permanent changes to the factory parts. Two sets of bushings are included (80-duromter [red] and 90-durometer [black]) so the customer can tailor the amount of differential support to their application.

In addition, the Steeda Mustang Differential Bushing Insert System installs in a couple hours and adds little to no perceptible increase in noise, vibration, or harshness.

It sounded like the right choice for us, so we headed to Gear Driven Automotive in Northridge, CA where owner Saul Gutierrez handled the install.

Photography by Damon Rivetti