Another NP203 Question

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CSFJ

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Actually, that was just the V8 trucks. 6 cyl trucks got the th350/np205 combo through the 70's.

It's easiest to get a complete setup from the same truck. It will all go in place of the 203 without transmission parts changes. Some years were flange front output while others were not (same for the 203). The t-case adapter uses a 27 spline sleeve. IIRC, the shifter is specific to the th350 combo as well. You can piece it all together, but it will cost a lot more. I bought two complete setups, one was only 100 bucks, I think the other was 175. That's without prop shafts, but anything that old is going to need rebuilt anyway. So new shafts aren't that much more in the grand scheme of things.
That's interesting about the 6 cylinder trucks, I don't believe I've ever run across that info before. Good to know.
 

bucket

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That's interesting about the 6 cylinder trucks, I don't believe I've ever run across that info before. Good to know.

They are often overlooked. When's the last time you ran across one? I think I've only seen one, lol.
 

CSFJ

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They are often overlooked. When's the last time you ran across one? I think I've only seen one, lol.

lol, I was going to add that to my post also, that I've never run across one.
 

theblindchicken

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Now I understand! Thank you! I was told once that the only 'operation instructions' for the TC were on the sticker on the visor. Mine no got. Never found any anywhere else.

Here's a link for the OEM NP203 Visor Label in my truck.

http://www.gmsquarebody.com/posts/338286/

Hope that helps.

(On mobile so link may not work. I'll check in the morning.)
 
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Thank you thank you thank you!
You must be registered for see images attach
 

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this may have been mentioned and I missed it, but have you tried adjusting the linkage and putting new bushings on the shift rods?
 

Snoots

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Yes. Even went as far to remove the shifter, disassemble it on a table, clean every piece, check for deformaties and burrs, carefully reassemble it with new bushings and adjust it. No slop. Works as it should. Just that blasted hang-up where I have to get underneath and jam it into gear from the LOC position. Probably something on the inside and I ain't going in there. Goblins!
 

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I found a salvage yard within a 2 hour drive that has several NP203's laying around. I can go through them and find one that has not been converted. Is there anything to look for other than obvious gear and chain wear that is viewable to the naked eye? If the oil looks ok and there isn't a bunch of metal in the bottom I should be ok, right?
 

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Need a quick answer here guys. About to send my son on a Friday afternoon class skipping salvage yard trip. We are going to pick up an unconverted 203 to swap into our faulty converted unit. They have several laying around, but don't know which ones are converted or non-converted. They will allow us to remove the tail housing to verify.

It's my understanding the TH350 NP203 should have 27 spline. Is that correct? I haven't dropped ours and wasn't going to until we had the replacement unit to go in.

Is there anything else to give my son for advice?

@bucket @crazy4offroad @CSFJ @yevgenievich

Thank you!
 

CSFJ

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Yes, th350 will have a 27 spline output shaft. Trying to think if there's anything else, but it's been over 20 years since I had one separated from a trans.
 

Honky Kong jr

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Yes, th350 will have a 27 spline output shaft. Trying to think if there's anything else, but it's been over 20 years since I had one separated from a trans.
I wanna say a Glide is 27 lol
 

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I believe that is correct but there is no such thing as a 4wd glide, is there?

I guess the main thing is that there isn't another major with the same spline count. Ford drops on drivers side and has 28 or 31 spline...GM drops on passenger side and is 27 or 32....from what I read.
 

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Yes 27 or 10 are your options, 10 being for standard only. I would have him pick up a set of seals for the adapter housing, should be a front and rear of the same size. I would have him get the shifter too since they are getting hard to find one that don't need disassembled and fixed up. I would also have him get the sleeve. They can get grooved like the harmonic balancer. You can have a machine shop weld it up on a rotating jig, then turn it down for a new seal surface.
 

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