Detroit Speed Assembled Center Section FN988 Torque Arm 31 Spline REM Polished Gear 070881-410DS-R

The Detroit Speed FN988 Torque Arm Differential delivers exceptional performance for builders and enthusiasts pushing the limits of their 3rd or 4th Gen Camaro or Firebird. By packaging the quiet, efficient gear set of the Ford 8.8 into a dropout center section with integral torque arm mounting, Detroit Speed offers the optimal differential solution for you Camaro/Firebird equipped with a 9” style axle housing.

ENGINEERED FOR STRENGTH

Detroit Speed’s FN988 Torque Arm assembly sets the standard for precision and performance in differential design. The integrated torque arm mount eliminates the need for additional brackets common in 9” axle housing swaps, improving the tight packaging constraints in 3rd/4th gen F-Bodies Each case is cast from high strength nodular iron and machined to exacting tolerances. Forged steel bearing caps further increase strength in high horsepower application. Assembled with a 31 spline True-Trac Differential, Ford Racing gear sets, high quality bearings and heavy-duty 1350 yoke ensures durability under modern power levels, making it ideal for high-horsepower LS and LT builds.

TRUSTED BY TOP INDUSTRY PROFESSIONALS

Designed with professional builders and enthusiasts in mind, the FN988 is trusted and used by many of the highest quality build shops in the country. The quiet, efficient operation offers a level of refinement consistent with the high quality builds. Its precise geometry, housing alignment, and superior materials make it the perfect foundation for Pro Touring and performance builds requiring exact tolerances and modern driveline control.

REM POLISHED GEARS

What is REM treatment? This polishing process creates a smooth micro-textured surface on the gearset for enhance oil retention properties. Commonly used by racing professionals looking for every advantage, the result of REM treatment is reduced heat and friction, increased component life, and quiet, efficient operation.

FEATURES & BENEFITS

• Engineered for Strength – Nodular Iron and Forged Steel bearing caps for high horsepower reliability.
• Quiet, Efficient Operation – transmit more power to the tires while eliminating gear whine.
• REM Treatment – reduced friction and heat, increasing component life.
• Ease of Installation – Dropout center installs into 9” housings and eliminates C-Clip axles.
• Integral Torque Arm Mounting – Refines the packaging and installation of a 9” housing in 3^rd/4^th gen camaro applications.
• 31-Spline Truetrac Differential – Delivers smooth, predictable power distribution and superior traction.
• 1350-Series Yoke – Heavy-duty construction for high-torque durability.
• Built to Detroit Speed Standards – Precision-assembled for performance, reliability, and perfect fit.
• Multiple Gear Ratio Options – 3.08, 3.31, 3.55, 3.73, and 4.10 gear ratios available, refer to part number for specific ratio.

FITMENT NOTES

• Fits: 1982–2002 Chevrolet Camaro & Pontiac Firebird (3rd & 4th Gen F-Body) with 9” axle housings
• Compatibility: Detroit Speed torque arm rear axle housing
• Differential: 31-spline Truetrac
• Gear Ratio: 4.10
• Yoke: 1350-Series
• Ideal For: Pro Touring, high-performance street, and competition builds