Here's a question I've been thinking about tonight..... Is it always true that 32-spline parts always have the same diameter? I'm thinking about transmission input/output shafts here. Is knowing that an output is 32 spline enough to guarantee that it will mate with a 32-spline input gear....??? This may include non-GM parts....BTW. What about some of the others.....like 27-spline stuff?? Is it always a match? (ps. - I'm not concerned for the moment about "stickout" lengths at the moment....just whether the splines are always the same shapes and overall diameters) This may have something to do with a T56 transmission and an Atlas 4 transfercase..... .............maybe.