Input shaft failure is a common problem in performance GM TH400 transmissions running with added horsepower. OE and aftermarket shafts simply don’t hold up in these conditions, leading to spline twist and shaft breakage.

Sonnax heavy duty input shaft 30280-02 is ideal for any street or strip application where maximum durability is needed from a stock-size, 1" dia. shaft. It is manufactured from 300M, high-strength steel with additional processing for resistance to fracture.

This shaft is intended for use with aftermarket converters with internal turbine support. Its forward drum spline is designed to be used with aftermarket drums with compatible 28-tooth spline, including Sonnax heavy duty forward drum 34554-01 and Smart-Tech^® drum module 34555-01K.

• High-strength 300M steel shaft undergoes additional processing to build-in resistance to fracture
• Ideal for high-horsepower street/strip applications running 1" dia. input shafts