Need help identifying t-case and tranny

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1987 GMC Jimmy

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Well, if it were me, I'd prefer a rock or something hit the cover rather than the TC body or flexplate teeth. They have fairly cheap steel inspection covers available.

https://m.summitracing.com/parts/sum-g3883b
 

dan3103

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The NP 203 was used in the full time 4x4 trucks in the 70's. If your truck has full time 4x4, it's got a 203.

A bit more info... It weighs about 200 lbs. It's often converted to part time 4x4 with addition of locking hubs in the front and parts in the transfer case. That will give you the addition of 2L as well as 2H, 4H, and 4L. They are pretty durable transfer cases, but probably not as strong as a NP 205.

Here's a link to some good info that shows differences between the 203 and 205...

http://chuckschevytruckpages.com/drivetrains.html
 
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HotRodPC

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That's a Th350 with the good torque converter. Don't lose that one, it's gold these days. Notice the mounting pads that use hardened bolt and nut to mount it instead of bolt lugs. Those are getting hard to find and high core charges for that type when you need a rebuilt one. And that is strongest Th350 converter. I even use those in race Th400 transmissions. I have one with a 3000 stall I've used in both Th350 and Th400's.

That is a Th350/NP203 Combo. Though the transfer case pics weren't all that great for ID, and to @theblindchicken, in the first pics that weren't very good at all I knew it was an NP203 cuz I knew it wasn't an NP208 or NP241C, so that leaves the choices of NP203 or NP205. NP203, speedo cable comes on on the driver side, NP205 comes in on the passenger side.

See, you do learn something new every day. And there are different tailshaft housings also and why it looked different than yours.
 

theblindchicken

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That's a Th350 with the good torque converter. Don't lose that one, it's gold these days. Notice the mounting pads that use hardened bolt and nut to mount it instead of bolt lugs. Those are getting hard to find and high core charges for that type when you need a rebuilt one. And that is strongest Th350 converter. I even use those in race Th400 transmissions. I have one with a 3000 stall I've used in both Th350 and Th400's.

That is a Th350/NP203 Combo. Though the transfer case pics weren't all that great for ID, and to @theblindchicken, in the first pics that weren't very good at all I knew it was an NP203 cuz I knew it wasn't an NP208 or NP241C, so that leaves the choices of NP203 or NP205. NP203, speedo cable comes on on the driver side, NP205 comes in on the passenger side.

See, you do learn something new every day. And there are different tailshaft housings also and why it looked different than yours.

Never noticed the difference in sides for the speedo cables. Do ya know any reasoning for the different tailshaft housings? My guess is just updated, improved designs. Appreciate the info! Thanks, @HotRodPC;
 

75gmck25

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Chad,

Your online info says your truck has a 454, but in 1976 the 400 was the largest engine available. Did the guy you bought it from explain when and why they swapped in a big block engine, and maybe mention what "vintage" 454 it is (e.g., pre-91 Mark IV vs. 91+ Mark V)?

Bruce
 

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as has been reported that a T-350 trans and a NP-203 transfer case. the first generation 203 had a one piece cast iron tail housing the second generation had a 2 piece aluminum tail housing. if it was me, I would get rid of both of them. highdesertranger
 

highdesertrange

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was a T-350 every offered behind a 454? highdesertranger
 

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To the best of my knowledge, NO. No big block for that matter that I can think of. In the Gen IV BBC, got Th400 or Manual transmissions until the 4L80-E.
 

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Looks like the OP (Huskerfan) has been gone for over a month. Maybe he's not coming back.

Bruce
 

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Well, that's OK too. Some just drop in at their convenience. Until then, we'll sit here and talk **** and muddy up the thread with other semi related tid bits. I'm sure the answer was given way up there so what happens way down here doesn't matter much. He may have dropped in, seen his answer and split without commenting. Some do that too and then we never know if they got fixed or not. :shrug:
 

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I was thinking of changing from my th350 and NP203
to my 700r (core for now) and NP205, What do you guys think?

Still need the 205 shifters and driveshafts.
 

CSFJ

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I was thinking of changing from my th350 and NP203
to my 700r (core for now) and NP205, What do you guys think?

Still need the 205 shifters and driveshafts.

Not a common combination, I can't recaĺl if there was a 205 with a 27 spline input. I think I've heard of them showing up behind a th350, but I'm not positve. In any event, if you can't find a way to use factory parts to mate them, it's apt to get expensive.
 

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205 did come behind th350 but you will need a spacer that you can get from off-road design to put it behind 700r

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