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Adapting np207 to 700r4?


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So not too long ago I got my hands on a 60 degree 700r4 trans that I intend to put in my comanche. Unfortunately the trans is 2wd so I need to get the parts to convert it to 4wd. My question is there any way to adapt the 700r4 to my 207 without breaking the bank on a Novak adaptor kit?20240303_190518.jpg.446e239513f5bcd554e5283833b8daef.jpg

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Your tail shaft may be too long, but if you’re lucky, you could get an adapter and NP241C that is driver side drop. That’s the route I would look into at least. You could get that adapter and transfer case out of an 88-98 GM truck with a floor shift transfer case. 

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I'm just trying to save a few bucks by not getting a different tcase if possible. I know my 207 is good. It's never let me down wh9ch is why I would like to adapt it. Plus I'm still staying with a 2.8. Only.. supercharged.

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9 hours ago, 89 MJ said:

Your tail shaft may be too long, but if you’re lucky, you could get an adapter and NP241C that is driver side drop. That’s the route I would look into at least. You could get that adapter and transfer case out of an 88-98 GM truck with a floor shift transfer case. 

I'm willing to pull parts off a junkyard 700r4 to adapt it to work. This 60 degree version is particularly hard to find because of the bellhousing pattern. But otherwise it is still a 700r4 like the rest of them

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4 minutes ago, The86manche said:

I'm willing to pull parts off a junkyard 700r4 to adapt it to work. This 60 degree version is particularly hard to find because of the bellhousing pattern. But otherwise it is still a 700r4 like the rest of them

Ok. I'm still worried that a 4x4 output shaft is supposed to be shorter than a 2wd output shaft. That is something to be sure of. I also have no clue if the 207 will bolt to the factory trans-transfer case adapter, which is why I recommended the NP241C, which would be hooked up to that transmission already. The spline counts might be different, engagement depths, bolt patters, etc. If you were to do an NP241C, you'll need to come up with some sort of shifter, as the shift pattern is the different from the Jeep ones. There are options for cable shifters out there. 

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Yep.  100% rebuild because the tail shaft is the last part to come out.

 

A junkyard transmission will have the 4x4 tail shaft but it will be a 27 spline chevy.  So you would either need a 21 spline Novak tail shaft for the trans or 27 spline input for the 207, which may not exist.  The trans to tcase adapter may not be clocked right for the Jeep case.

 

You're better off getting a chevy case to go with the transmission. 

 

You would want parts from 82-96.  GM redesigned the transmission case for the 97 model year so parts won't bolt up across that boundary.

 

82-87 will have a passenger drop NP208 case.  The half ton pickups switched over to driver drop in 1988.  The K5 and Suburban stayed passenger drop through 1991 but then went driver drop in 92.  Right around then the NP208 became the NP241.

 

3/4 and 1 ton puckups came with the TH400 or 4L80 so no compatable parts there.

 

So grab a transmission and floor shift tcase from a 88-96 1500 pickup or 91-96 Tahoe, Yukon, or 1500 Suburban.  Rebuild the 60° 700R4 using the donor tail shaft and stock tcase and you'll be golden.

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12 hours ago, derf said:

Yep.  100% rebuild because the tail shaft is the last part to come out.

 

A junkyard transmission will have the 4x4 tail shaft but it will be a 27 spline chevy.  So you would either need a 21 spline Novak tail shaft for the trans or 27 spline input for the 207, which may not exist.  The trans to tcase adapter may not be clocked right for the Jeep case.

 

You're better off getting a chevy case to go with the transmission. 

 

You would want parts from 82-96.  GM redesigned the transmission case for the 97 model year so parts won't bolt up across that boundary.

 

82-87 will have a passenger drop NP208 case.  The half ton pickups switched over to driver drop in 1988.  The K5 and Suburban stayed passenger drop through 1991 but then went driver drop in 92.  Right around then the NP208 became the NP241.

 

3/4 and 1 ton puckups came with the TH400 or 4L80 so no compatable parts there.

 

So grab a transmission and floor shift tcase from a 88-96 1500 pickup or 91-96 Tahoe, Yukon, or 1500 Suburban.  Rebuild the 60° 700R4 using the donor tail shaft and stock tcase and you'll be golden.

This is all good to know info.

Novak does sell a kit to make the 700r4 and 207 bolt together but it's $700 for a output shaft and billet plate. I don't want to spend 700 for that.

Trying to find a different input for the 207 kind of turned up fruitless so far.

At the very least I intend to rebuild the 700r4 anyway so I'll be in it regardless. I was just trying to save some cash and make it work with what I got instead of having to get more parts. And most yards charge an arm and a leg for drivetrain components around me.

So I guess I'll have to shower around for a proper drive drop tcase.

I will say the transmission is from an 88 s10 if I didn't mention that.

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9 hours ago, The86manche said:

This is all good to know info.

Novak does sell a kit to make the 700r4 and 207 bolt together but it's $700 for a output shaft and billet plate. I don't want to spend 700 for that.

Trying to find a different input for the 207 kind of turned up fruitless so far.

At the very least I intend to rebuild the 700r4 anyway so I'll be in it regardless. I was just trying to save some cash and make it work with what I got instead of having to get more parts. And most yards charge an arm and a leg for drivetrain components around me.

So I guess I'll have to shower around for a proper drive drop tcase.

I will say the transmission is from an 88 s10 if I didn't mention that.

An S10 (including an S10 Blazer) would have a driver drop case that would bolt up.  Still need a 4x4 transmission to supply donor parts.

 

Trying to keep the Jeep 207 may be more trouble than it's worth. 

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