RTS Differential, Full Spool 40 Spline, True Race Lightweight Ford, 9 in, Each

RTS Lightweight True Race Spools RTS Lightweight True Race spools give you the traction that you need by locking the axle shafts together, forcing your rear tires to turn at the same speed. They're CNC-machined from forged chromoly steel to provide a more rigid ring gear mounting. This eliminates the gear failure caused by case deflection or differential side-gear failure. Fits 3.250″ bore aftermarket case's. Features: • Machined from 8620 forged steel • Lightened to reduce rotating weight • Broached 40 spline with 45° pressure angle • Heat treated • Finish machining after heat treat to bring surfaces within specifications: • Designed In House