What is the output spline on the Allison and what is it on the zf 6? And does anyone know of a pass side drop t case that will bolt up to the zf6? Other then an atlas. Really don't want to spend 3k+ on a t case.
Zf/Allison output spline count.
- Thread starter catman3126
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Is this the 205 that was in the square body 3500's 89 to 91 or something that had the VSS on them? wouldn't that be 32 spline?
205's were in the cab and chassis until 91 yes. But they were in a wide variety of vehicles for many years before that.
so is there a kit to make these 205s a 29 spline input? I would need one of the 205's that had the VSS which I looked for when I found the NP241C I use now. Ideally that would be the best since I would just have to change out the input shaft to make it a 29 spline and bolt it up and have my VSS signal. now if someone make a NP241C 29 spline kit that would be even more tits since I have it already.
The ALLISON and ZF6 behind a DURAMAX are 29 spline. The NP205 can be mated up to an ALLISON with a clocking ring, or custom rear housing(if you can find one still), and a FORD 29 spline input shaft for the 205 case. GM used a 27 for 1500's, and 32 for 2500/3500's, but FORD used the large 29 spline even early on behind there 250/350 platform. Member pussow over at DP had a 205 mated up to his ALLISON in his DURAMAX swapped truck(mid 80's passenger side drop front axle), but I believe he said clearance to the trans around the driveshaft was TIGHT to say the least. As to the speed sensor, you can run the late model 205 from a GM since it used a VSS in it. Others that have done this swap though have opted to move the VSS up the output shaft of the trans. I know it was posted taht at least teh A40 6 speed TCm was NOT happy with the gear ratio change in reverse. He changed it in the TCM from 2.72:1 to the 205's ratio, but in reverse and low range it would limp everytime he said.
Dmax 29 spline is bigger OD then 32. Turn down, respline, treat. Couple guys have done it with cummins/Allison swaps
Yes 205 from 91 square body has the electric vss. Rare, just sold the only one I've ever seen. They do exist tho!
Interesting. Didn't know the ford 29 was same size as dmax... That's a much better option. Guess that's one reason not to let this ford 205 go...
thought about that but its a reg cab short bed so I'd hate to get too stretched out there.
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This was another option I thought about was if I could change the input shaft does anyone know if it will fit internally and get me the right gear pitch internally? also doe the input shaft come as one piece with the gear machine on it? if not I could just machine the shaft and cut the correct internal splines. (machine shop at work with anything you could want) but if it has the gear as one piece with the shaft that would be a little tough. (which I think is how it is made)
But since I would be doing a ZF6 swap I should have plenty of room and if I had VSS off the t case out put that should have no problem and I wouldn't be running a TCM.
Yes I tried to find one for the LS swap with the 4l80 I did last winter. I just wanted the tougher cast t case. no luck.
The only other option I can come up with it is to run a ford Dana 60 diff from the 90s OBS and the factory ZF and T case. Or just say Fack it and run a big ass turbo on the LQ4 6.0 and see what that does lol. IDK I think it would be really cool to have a ZF6 duramax short bed reg cab K10 with a built motor dmax in it. what would be more wicked the 80MM t6 flange S480 turbo LS motor? or a built motor duramax with a big single on it in that same short bed K10?
Could you machine the spot where the cable drives the speedo and make it accept a vss sensor?
I would imagine so, what did you have in mind for a t case? Is there something that doesn't have VSS that you know of that would work? Or just doing the shaft swap into an older 205?
For a ZF6 swap another option would be to use an inline cable operated speed sensor. A few companies still sell them that go in a speedo cable, and it has a magnetic pickup in it. This way all you need to find is a 205 case, and a 29 spline input shaft for it.