Originally Posted by dnkynrbk

I think its 6 inch. I will try to measure mine and get back with you

Originally Posted by Bro Inc

Most common are 4" 32 spline, and 9" 27 spline.
Some not so common are 9" 32 spline, 13" 32 spline.

I've seen a shelf of th400 output shafts in an old abandoned shop and there are at least 20 different types. Like 13 spline something for a jeep, Jaguar, Hummer (the real ones), etc. I'm pretty sure I've seen a whole th400 with a tail longer than 13" too.