• Fits all Super 8.8" IRS axles in 2015-2018 Mustang
• Note: does not fit earlier 8.8 axles
• Bill of material:
  • OEM pinion bearings and races
  • OEM Differential bearings and races
  • Pinion and Differential Shims
  • Crush sleeve
  • Pinion nut
  • Pinion seal
  • Ring gear bolts
  • Gear-marking compound

2015-2018 Mustang 8.8 inch 3.55 Ratio Ring and Pinion Gear Set

M-4209-88355A

• Fits 2015-2018 Mustang 8.8-inch IRS center section. Will not fit earlier model years.
• Includes OEM crush sleeve and pinion nut
• Requires M-4210-B3 2015-2018 Mustang 8.8-inch ring-gear and pinion install kit sold separately
• Superior forged construction
• Black oxide coated to resist rust
• Made in United States in Ford's Sterling Axle Plant
• OEM Quality - our superior surface finish, hardening and manufacturing consistency provide the strongest and quietest gears in the market.
• Requires aftermarket calibration if vehicle is not originally equipped with this gear ratio
• Note: Vehicles originally equipped with 3.15 rear axle ratio must upgrade the differential to use this gear set. Use differential M-4204-MT or M-4204-M

• Fits 2015-2018 Mustang 8.8-inch IRS center section. Will not fit earlier model years.
• Includes OEM crush sleeve and pinion nut
• Requires M-4210-B3 2015-2018 Mustang 8.8-inch ring-gear and pinion install kit sold separately
• Superior forged construction
• Black oxide coated to resist rust
• Made in United States in Ford's Sterling Axle Plant
• OEM Quality - our superior surface finish, hardening and manufacturing consistency provide the strongest and quietest gears in the market.
• Requires aftermarket calibration if vehicle is not originally equipped with this gear ratio
• Note: Vehicles originally equipped with 3.15 rear axle ratio must upgrade the differential to use this gear set. Use differential M-4204-MT or M-4204-M

Ford Performance 2015-2017 Mustang 3.73 Ring & Pinion Plus Install Kit

M-9000-88373A

A great value to install a 3.73 gearset in your 2015-17 Mustang. Includes 3.73:1 gearset M-4209-88373A and complete install kit with bearings M-4210-B3

Note: 3.15 ratio differential not compatible with 3.31, 3.55 and 3.73 ratio gears. Use differential M-4204-MT or M-4204-M

Requires aftermarket calibration if vehicle is not originally equipped with this gear ratio

Fluid is not included