sm465 to np208

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Swims350

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ok guys what exactly is needed to mate a sm465 to my current np208 ransfer case? I'm pretty sure it's a 27 spline dal that was behind a th350 or 700r4, my guess 700r4 factory, someone swapped to th350 because I found the spacer in the bed from the kits to put a th350 in place of a 700r4.

From what I've read it needs to be a newer sm465 with 32 spline and then get the right adapter and 32 spline shaft for the t-case? tear the case apart and swap it to 32 spline and good to go?

What about an older sm465 I read they had 10 spline and have a coupler for an np205 10 spline to 10 spline. If that's the sm465 I get then I have no choice but to get a np205 case? or can the sm465 be swapped to 32 spline then have to swap the case and adapter to 32 spline and make it work like above?

I've got the 208 and it's turning out hard to find a trans to put in this. I know a 700r4 would be a direct bolt in, but don't seem to be any around. I also know that if I get any 2wd th350 I could swap shafts and use the spacer and make it work. I'd rather have the th350 but I'd rather not rip into it and change shafts, I've done it before, didn't turn out so well.

I really think a reg. 4wd th350 would be too short, it'd make me move my crossmember forward thus making my rear driveshaft too short.
 

87scotty

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Swims350

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I can't find a th350 or 700r4 let alone a th400
 

Swims350

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honestly I need something ready to go as I'm not trans builder, and the local guy would want 700-1000 to build one.
 

Swims350

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manual trans I could maybe handle doing a rebuild on. auto's I'm not that good on I got the th350 handbook on rebuild and HP mods, but still last one I tried I ruined somehow.
 

bucket

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IMO, just keep looking. If you can find an adapter and shaft to mate your 208 to a different trans, they will likely have the whole trans/t-case combo wrapped around them.
 

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And all the setups with a 208 use the same length driveshafts. The adapters make up the differences in trans lengths. Swapping in a 203 or 205 setup will involve changing driveshaft lengths.
 

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And all the setups with a 208 use the same length driveshafts. The adapters make up the differences in trans lengths. Swapping in a 203 or 205 setup will involve changing driveshaft lengths.


yes but if I put in a th350 to an np208 it's shorter then a 700r4 so I'd have to move the crossmember forward making the rear shaft too short.
 

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bucket

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yes but if I put in a th350 to an np208 it's shorter then a 700r4 so I'd have to move the crossmember forward making the rear shaft too short.

That just depends. The original th350 that would have been used with a 208 would be the same overall length as the others. An earlier th350 would not work because the output shaft is WAY too short. Using a 2wd th350 with the spacer should make it the correct length I think.
 

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yes that is the thing as far as I know they didn't have a th350 with a 208 behind it, the old ones like you said are short. I can pick one up for $100 but I thought it looked too short. the 2wd with the right shaft, or a cut down one and the spacer makes it the same as a 700r4 I had one in my 88 obs truck.
 

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Between Baldwin's, J&J's and a bunch of other junkyards and the Ad Bulletin up here, I know we could find the stuff for a direct swap. The trans out of my camo truck would need some work, and you know it's seen just a little bit of abuse lol. That blue truck I had briefly had sm465 to 208 so there should be a million out there. What's the cab already set up for, standard or auto?
 

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cab is auto 2wd, there's one sm465 and 208 combo for sale they want $300 I don't have any cash like that now. if I go with an auto it has to be 700r4 or most likely a 2wd to get the kit and the right shaft and spacer to make it go in place of the 700
 

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They did offer the th350/208 combo for a few years. '81 would have been the most common because the 700r4 was not offered yet.

I think $300 is about as good as you're going to find, unless you can get a "buddy" kind of deal somewhere.
 

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