The T-14 is a 3 speed transmission with a cast iron case. I has a casting number of T14A or 1302 and a 1 1/8" 10 spline input shaft. The I6 T-14 has a 1 3/8" 6 spline output while the V6 T-14 has a 1 3/16" 10 spline output. Input shafts lengths also vary between the two applications.