A727 Chromoly Slip Yoke 30-Spline 1350 Series 3-3-3931X

A 1350-series driveshaft slip yoke, part number 3-3-3931X (Sonnax cross-reference T3-3-3931HP), forged from chromoly and fully CNC machined. It has a 30-tooth spline, a 1.680 inch journal diameter to suit a 1350 U-joint, and measures 6.30 inches from the U-joint centerline to the end of the yoke. There is no counterbore.

It fits the Chrysler A727 TorqueFlite automatic, the A833 four-speed manual, and Tremec T56 transmissions built with a 30-spline output shaft. Count the output shaft splines before ordering; many T56 applications use a different spline count.

A chromoly yoke is the upgrade when the factory yoke is the weak link: a cracked or twisted yoke, a worn seal surface that keeps leaking at the tail housing, or a car making more power than the stock driveline was built for. Moving to 1350 also means a stronger U-joint. Confirm the driveshaft has a matching 1350 weld yoke, check the seal surface for nicks before installing, lube the splines, and fit a new tail housing seal at the same time.