31-Spline HD Third Member Assemblies
- HD ( Heavy Duty)
- Can handle up to 850 HP but restricted to 700 HP because of the factory 31-spline axles
Note: This Third Member Assembly also includes the U-joints/U-Bolts.
Ready-to-Install Third Member Assemblies
Speedmaster Ford 9-in. Complete Third Member Assemblies feature a Torque Worm 6-pinion limited-slip or full-spool differential in 28 and 31-spline axle shaft configurations. Third Member Assemblies are available in your choice of the most popular gear ratios and contain a new A356-T6 aluminum case that is assembled with all-new bearings, seals, heavy-duty ring and pinion, one-piece billet (through bolt) main caps,12-point bolts, u-joints/u-bolts, and precision-machined 1350 billet steel yoke. The 1350-series yoke is ideal for all forms of motorsports ranging from V8 SUPERCAR through Group 1 Drag Racing.
HD-style cases are rated at 850 HP but limited due to the size of the spline axle shaft.
Ultra HD-style cases are rated at 1200 HP but limited due to the size of the spline axle shaft.
LSD (Limited Slip Differential)
HD ( Heavy Duty)
Note: Each Third Member is to be used with a mineral-based oil of a range of EP140 Extreme pressure at a minimum. DO NOT USE split grades eg. 85/140 (these are not recommended). Failure to use the correct oil can result in gear damage, noise and may void your manufacturer's warranty.
WARNING: Motor vehicles contain fuel, oils and fluids, battery posts, terminals and related accessories which contain lead and lead compounds and other chemicals known to the State of California to cause cancer, birth defects and other reproductive harm. These chemicals are found in vehicles, vehicle parts and accessories, both new and as replacements. When being serviced, these vehicles generate used oil, waste fluids, grease, fumes and particulates, all known to the State of California to cause cancer, birth defects, and reproductive harm.
WARNING: Some dust created by power sanding, sawing, grinding, drilling, and other construction activities contains chemicals known to the State of California to cause cancer and birth defects or other reproductive harm. Some examples of these chemicals are: lead from lead-based paints, crystalline silica from bricks and cement and other masonry products, and arsenic and chromium from chemically treated lumber. Your risk from exposure to these chemicals varies, depending on how often you do this type of work. To reduce your exposure, work in a well-ventilated area and with approved safety equipment, such as dust masks that are specially designed to filter out microscopic particles.
WARNING: The wires of these products contain chemicals known to the State of California to cause cancer and birth defects or other reproductive harm. Wash hands after handling.