242 t case swap

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dirtautoguy

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So maybe this will be a super easy question maybe not…

I have a 96 k1500 rcsb. It has 285000 Miles. It’s had a lot of work done to it and there’s a lot more planned. One of which is the transfer case. Iv owned the truck for about 11 years and it has leaked from the tail shaft and front output shaft. I know that it has been run low or with no oil because it had very little oil in it which I didn’t discover untill after owning it for a while. When I changed the oil for the first time the oil had a lot of glitter in it. But as a high school kid I filled her up and ran it and it’s still going today

It still works pretty fair however roughly 2 winters ago it started popping out of 4wd and having a hard time engaging 4wd sometimes. Iv had the intention of rebuilding the original t case as I believe it is within my skill level.

Here’s the question. Near me there is a person selling a np241 t case out of a 96 2500 long bed. It has 85000 miles on it and appears to be in good shape for $100.

First of all do the 1500 and 2500 trucks both use the 241 t case?

is there anything specific I should watch out for on these cases? If I were to get it I would probably replace all the seals accessible without taking it apart just for good measure

Any other thoughts? Good buy? Bad buy? Did I miss something?
 

Schurkey

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Popping out of 4WD is generally worn-out plastic pads on the shift fork.

The pads wear out due to abrasives in the fluid. At least, that's what I was told when my manual-floor-shift transfer case was doing that 20+ years ago. The other rumor is that the Auto-Trac transfer case lube is just Dexron III-spec fluid, but with blue dye instead of red. No promises on either.

You'd need to research the differences between the '241 and '242 cases.
 

dirtautoguy

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I’m fairly positive my truck has a 241 t case. It is manual shift.

Iv heard that as well. Iv also heard those pads get messed up if it’s gotten hot. I’m not saying mine is on its last leg but it certainly is not fresh and is declining
 

dirtautoguy

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Iv been doing some research and found some things. Apparently a 241 t case of a 2500 will have a 32 spline input shaft while a 1500 truck will have a 27 splined shaft. Can anyone confirm this?

If this is the case it will not work for me
 

Nad_Yvalhosert

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Iv been doing some research and found some things. Apparently a 241 t case of a 2500 will have a 32 spline input shaft while a 1500 truck will have a 27 splined shaft. Can anyone confirm this?

If this is the case it will not work for me

I can confirm:
1500/2500LD trucks with the 4L60 transmission has a 27 spline output.
2500/3500 trucks with the 4L80 have 32.
If the 2500 has a 4L80, notta gonna work...

Here's my issue. My '89 1500 has a manual tranny (32 spline) and a 241 and I want to 149 (AWD Escalade) swap it. 149 has the 27 spline...
 

Nad_Yvalhosert

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Iv been doing some research and found some things. Apparently a 241 t case of a 2500 will have a 32 spline input shaft while a 1500 truck will have a 27 splined shaft. Can anyone confirm this?

If this is the case it will not work for me

I do have a suggestion. It's likely that the two 241 cases are physically the same, but the input and output gears are different. What about tearing down both, and installing your 27 spline input and output shafts into the 32 spline unit?
 

TreeGeared

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Honestly you are probably better off just finding a half ton case. You could make the other work but would likely involve swapping yokes or driveshafts and using u-joints with different size caps. Been there, done that, have a bunch of driveshafts sitting in the corner of the barn.
 

Supercharged111

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I do have a suggestion. It's likely that the two 241 cases are physically the same, but the input and output gears are different. What about tearing down both, and installing your 27 spline input and output shafts into the 32 spline unit?

This, if the 2500 case in question is a screaming deal. Or the only deal. I swapped a 32 spline input shaft and bearing into my 243 case when I 4L80 swapped my 1500 and it was easy. Just make sure to get the new plastic shift fork dealies that Schurkey mentioned, mine were tore up on the one fork. I only replaced what was worn though, figured the factory stuff was better than the aftermarket.
 

dirtautoguy

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It’s a $100 and supposedly has 85000 miles on it but I can’t confirm that. I’ll ask about the truck it came out of.

The thing is if Iv gotta tear it down to make it work in my truck then I feel like I may as well get a rebuild kit and just rebuild mine.

If I can find one in decent shape that will bolt on I’ll go that route otherwise I’ll just rebuild mine
 
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