Help mateing a US Gear Overdrive

[racprops]

I am still working on joining my 4L80E to my US Gear Dual Range over drive.

It seems there is no reasonable way to do it.

First I have tried locating companies that can/will CUT splines…the costs are more than the two transmissions together.

So my best idea is to locate a certain Ford C6 4X4 OEM 15.5 31 Spline output shaft, then machine it so that is can be fitted tightly into a TH400/4L80 slip sleeve and two pins drilled and pressure fitted though the combination.

Or this one could also work: FORD C6 Automatic Transmission Output Shaft. 2 Wheel Drive 31-26 SPLINE

I want this one shaft as it is wider than the splines a short way back and should be possible to either machine or grind it down as they do crank shafts to size.

The best of all worlds would to find a shop that can cut a 400’s 32 splines into it, but it would take a mill and indexer and a good workman, and again the costs seem to be way too high.

Funny as there are a bunch of DYIs videos on Utube…

So I am looking for this shaft, and I can use a damaged one as long as the main 50% of it is good.

Rich

[Piotrsko]

Series of odd ex hotrodder raving lunatic thoughts: there should be tranny rebuild places that have the shaft or access to new. Borgwarner 13-XX transfer cases come to mind also since I have one in the ranger from a C6, but you wouldn't be stuck with a C6 unless the 5 speed sticks use a different output spline. Should go out to the shed and count splines on the 727 shaft if I can find it because I cant remember if it fit by mistake.

[racprops]

Or this one could also work: FORD C6 Automatic Transmission Output Shaft. 2 Wheel Drive 31-26 SPLINE

I want these shafts as it is wider than the splines a short way back and should be possible to either machine or grind it down as they do crank shafts to size.

Most shafts are machined behind the splines so there is clearance for over stroking of the slip yoke. Even these two have some back cutting but not as much as most standard shafts.

Rich

[Piotrsko]

Thinking about it some more: the C6 has a bolt on case extender that you remove for adding the borgwarner. That should have the shaft you want in the proper configuration. Find a 4wd option truck that is 2wd at pick a part, it's like 3bolts to remove and pukes tranny fluid.