Differential Bushing Insert System

The Steeda S550 Mustang Differential Bushing Insert System - Street to Full Race Combo Kit is engineered to enhance the performance of the S550 Mustang's rear IRS suspension. This kit features a combination of urethane and billet 6061 aluminum bushing inserts designed to limit differential movement, thereby increasing traction and eliminating wheel hop. Unlike competitor kits that may significantly increase NVH (noise, vibration, harshness) and require extensive installation time with permanent modifications, Steeda's system installs in under an hour with little to no increase in NVH for the urethane options. The kit includes three bushing options: red 'street' (80 durometer), black 'performance' (90 durometer) urethane, and billet aluminum 'race' inserts. The system includes bushings for both front and rear differential mounting locations, along with Grade 10.9 hardware and zinc-plated washers. Note: This system does not fit the GT350 or Mach 1 models. Due to OE subframe bushing changes, it will also not fit 2021 GT500 or 2022 Mustang models.