Steeda Mustang Adjustable Diff Bushing Insert System
Differential inserts support the original front and rear mounting bushes to reduce differential movement, pinion-angle changes and wheel hop. No drilling, cutting or pressing is required, and the modification is reversible. Steeda estimates installation at one hour or less.
Street and race options
Urethane kit 555-4443 includes red 80-durometer street inserts and firmer black 90-durometer inserts. Noise changes vary between cars because the differentials themselves vary in gear whine. Aluminium race kit 555-4440 removes more compliance but increases drivetrain noise and is intended for track use. Street to Race packs include both materials: 555-4442 for GT and 555-4444 for EcoBoost. Older 555-4439 is discontinued.
Grade 10.9 hardware and zinc-plated washers are included. Designed and manufactured in the USA.
Instructions and videos
Related vehicles
- Mustang S550/S650 from 2015, including GT, EcoBoost, Bullitt, Mach 1, Dark Horse, GT350, GT350R and GT500
Select the engine-specific combination pack where applicable.
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