GM TH350 4wd to Toyota Gear Drive 21 Spline Transfer Case Adapter

 

The GM TH350 3 speed automatic transmission adapter to the Toyota Truck gear driven transfer case is 3.50”. The adapter material is 356 T-6 heat treated aluminum alloy. Our adapter kit will include the Adapter Housing, a 27x21 coupler, nylon bushing, cover plate, gaskets o-ring, seal, fastening hardware and adapter instructions.

 

 

The adapter assembly fits the Toyota Truck 21 spline gear driven transfer cases. This transfer case has a male 21 spline input shaft and can also be identified by 7 bolts attaching the tailhousing to the transfer case.

 

 

This adapter kit is designed for exclusive use with the 4wd GM TH350 automatic transmission. This GM automatic was commonly found stock in vehicles from 1969-81. The Turbo Hydramatic 350 three speeds automatic is one of the most transmissions available in GM 4x4 trucks. The stock 4wd output shaft protrudes from the back of the case approx 1”. 1980-81 model TH350 4wd output protrudes out 2.750”. And this TH350 also uses a lock-up torque convert, and was always used with an aluminum transfer case. We recommend the 1980-81 model not be used.