Ford NP208 Interchange / 27 Spline Output Shaft Th400

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MadOgre

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You could also find any round input styled 205,208,241 and change the input gear to 27 splines
 

silverscottsk10

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What have you done to your square lately??

I wouldn't have believed it if I hadn't seen it. Well I guess any 205 from a TH350 or a 208/241 from a TH350 or 700R4.


I wasn't lying to you lol

You could also find any round input styled 205,208,241 and change the input gear to 27 splines


Any 208 would work since my internals are all good
I think I'll start a thread and if you could school me there so we don't clutter this more
@HotRodPC could one of you move this into its own thread?
 

HotRodPC

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I wasn't lying to you lol




Any 208 would work since my internals are all good
I think I'll start a thread and if you could school me there so we don't clutter this more
@HotRodPC could one of you move this into its own thread?

Yes, let's get a thread going about this. I too and surprised to see this 27 spline in the Th400. Now there is such an animal that I am aware of. It's called a Th375, which is a Th400 all day long but it has a 27 spline Th350 output shaft, and the tailshaft housing says, THM375 on it. However, that length is much to long for a Transfer case adaption. Makes me wonder if it's aftermarket, or if there is something out there I wasn't aware of too.
 

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Yes, let's get a thread going about this. I too and surprised to see this 27 spline in the Th400. Now there is such an animal that I am aware of. It's called a Th375, which is a Th400 all day long but it has a 27 spline Th350 output shaft, and the tailshaft housing says, THM375 on it. However, that length is much to long for a Transfer case adaption. Makes me wonder if it's aftermarket, or if there is something out there I wasn't aware of too.

I was wondering if its not a 2wd with a cut down output shaft ?
 

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I was wondering if its not a 2wd with a cut down output shaft ?

To use the adapter to make a Th350 match the length of a 700r4 and not have to cut your driveshafts or move your crossmember, yes, it's a 2wd 6in passenger car output shaft that you cut down. Approximately 1.25 inches IIRC. Can't be the 9in intermediate 2wd output shafts used in squares. Cuz you'd have to cut off like 4.25 inches, then there is no splines left. So it must be a 6in 2wd passenger car output shaft.
 

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To use the adapter to make a Th350 match the length of a 700r4 and not have to cut your driveshafts or move your crossmember, yes, it's a 2wd 6in passenger car output shaft that you cut down. Approximately 1.25 inches IIRC. Can't be the 9in intermediate 2wd output shafts used in squares. Cuz you'd have to cut off like 4.25 inches, then there is no splines left. So it must be a 6in 2wd passenger car output shaft.

I just figured that would be the most plausible thing as why would someone go to all the trouble of building a th400 with a custom 27 spline shaft? And then I remembered that all the driveshaft slip yokes are 27 splines regardless of what transmission it is.
 

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True, but the Th350 output shaft isn't going to fit into a Th400 at all. The sun gear is different. Unless he has something that I'm not aware of, that is an aftermarket output shaft he has in his Th400, cuz it's to short to be the THM375 output and it's also like 9 inches long. I am interested in finding out where he came up with that 27 spline 4x4 output for a Th400. I have a feeling it's aftermarket.
 

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True, but the Th350 output shaft isn't going to fit into a Th400 at all. The sun gear is different. Unless he has something that I'm not aware of, that is an aftermarket output shaft he has in his Th400, cuz it's to short to be the THM375 output and it's also like 9 inches long. I am interested in finding out where he came up with that 27 spline 4x4 output for a Th400. I have a feeling it's aftermarket.


Im saying that a 2wd th400 transmission with a 6" tail shaft will have the 27 splines for the 2wd slip yoke. Cut that down to match the length of a 4wd out put shaft and voila! A 27 spline 4wd th400 ???
 

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I know at some point there was an aftermarket "conversion" shaft, which is what that more than likely is.

The amount of "stickout" that shaft has will determine what t-cases you can easily use.
 

crazy4offroad

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Could have been an RV option, like the 375 or 475 but they have straight cut gears, a little more noisy in 1st gear.
 

bucket

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Im saying that a 2wd th400 transmission with a 6" tail shaft will have the 27 splines for the 2wd slip yoke. Cut that down to match the length of a 4wd out put shaft and voila! A 27 spline 4wd th400 ???

My 2wd th400's have had 32 spline outputs. Never seen a factory th400 of any kind with a 27 spline actually.
 

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Well there goes that idea. I thought all drive shaft slip yokes used the same 27 splines.
 

bucket

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Well there goes that idea. I thought all drive shaft slip yokes used the same 27 splines.

I guess mine weren't actually a slip yoke though, but the bolt-on yoke can be removed and a slip yoke simply slides in place.

An actual slip yoke th400 must be a rare bird these days, as they would have been in older passengers cars and pickups. I think they were all 32 spline though.
 

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I know at some point there was an aftermarket "conversion" shaft, which is what that more than likely is.

The amount of "stickout" that shaft has will determine what t-cases you can easily use.

Yep, that's what I"m thinking. I know for a fact it exists and it is aftermarket.
 

silverscottsk10

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Man you guys been busy, this transmission has papers I got from the po from a rebuild I believe, but I've never been any farther than replacing torque converter and filter,
I'll have to look for some pictures or numbers on it if that will help,
But it's a cool idea of it is aftermarket
 

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