Will NP241 innards work in a NP208 to replace worn parts?

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mtnmankev

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84 K-10 with TH350 trans and NP208 transfer case.
The front output yoke has developed a HORRIBLE leak and upon removal of the driveshaft I find a ton of slop in the yoke.
Of course I suspect bearings have failed, and I have a rebuild kit on hand waiting for the winter mud season to end so I can put the truck down to do the repairs and use my 2WD truck to get out and in.

The big question is, if the front output shaft itself is worn bad, can I swap the one from a 241 I have laying around (providing it's good) ?
I searched online and cannot find a source for a 208 front output shaft in case I need one.

Also, the planetary gear set in the 208 sings like an angry woman opera singer when in low range, so obviously I will need to replace the planetary.
From research I did, obviously the 241 planetary is different and most likely won't interchange, and the gear ratio is slightly different but that would not bother me a bit if it was different by a small margin.

Are there any other things I need to be aware of or look for when the 208 is finally disassembled ?
 

bucket

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I don't believe anything really interchanged with them. Just the unit as a whole is a direct swap.
 

mtnmankev

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The overall condition of the 241 I have is questionable.
And I don't feel like disassembling it right now to peek inside.
If I tried to just do a swap, I would most likely find a difference in the input splines, if I recall correctly.
And with my physical shape being what it is, I MIGHT manage to do one remove and one install.
I can't be playing the musical transfer cases game.
 

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The t-cases will interchange if swapped. I went from a 208 to 241 and could reuse both driveshafts. Just have to make sure the spline count is the same. 28 vs 31.
Is the 241 a right side drop and mechanical speedo?
 

mtnmankev

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I know it's mechanical speedo, and should be a right hand drop.
I will remove the tarp tomorrow keeping the snow off it and verify.
Thanks !!
 

mtnmankev

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It IS a right hand drop 32 spline input, so I get to buy a 27 input shaft and install it.
Both my 208 and the 241C have a 32 spline rear output, and despite the differences in tailhousings, I SHOULD be able to get away with not changing driveshaft length.
Correct me if I am wrong.
ANOTHER QUESTION _- what about the T case to trans adaptor?
Will I need to change the adaptor to bolt the 241 to my TH350 ?
 

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It will bolt right in using your current adapter and shafts.

So it's a 32 spline input and you will be installing a 27 spline input? Got plans for the 32 spline input?
 

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It IS a right hand drop 32 spline input, so I get to buy a 27 input shaft and install it.
Both my 208 and the 241C have a 32 spline rear output, and despite the differences in tailhousings, I SHOULD be able to get away with not changing driveshaft length.
Correct me if I am wrong.
ANOTHER QUESTION _- what about the T case to trans adaptor?
Will I need to change the adaptor to bolt the 241 to my TH350 ?
Ok, then you have a 241 from a 3/4 ton. All should bolt up after you charge the output to 28.
 

mtnmankev

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As of yet, no plans for the 32 input.
Since I am afraid the 208 front output shaft is trashed because it went too long on worn out bearings, and I can't find a front output shaft online, I probably won't be rebuilding the 208 as originally planned.
It will most likely get parted out for the good used parts and the rest for scrap or welded in metal art sculptures.
I am going to try and disassemble the 241 today to inspect it inside and hopefully I won't need to buy a herd of parts.
I don't know yet if the 32 input has the wide or narrow bearing surface.
And I'm not sure about bearing width on the 27 .....
And speaking of bearings, maybe I will get lucky and the bearings in the 208 rebuild kit I have on hand will fit most of what the 241 uses so I can start with a freshly built case.
Even have a brand new chain for the 208 that won't get used.
 

mtnmankev

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Ok, then you have a 241 from a 3/4 ton. All should bolt up after you charge the output to 28.

I won't change the output to a 28 as my current driveshaft slip yoke is a 32.
Besides, that would mean I would have to buy a mainshaft.
 

RoryH19

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I won't change the output to a 28 as my current driveshaft slip yoke is a 32.
Besides, that would mean I would have to buy a mainshaft.
Oh, ok. You already have a 32 spline drive shaft.
 

mtnmankev

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I checked the 208 chain against the 241 and they are the same, that saves some money.
Gonna drop the 208 from the truck and verify what the spline count is before I order a new input.
Will need to order a bearing kit for the 241 as it uses heavy duty ball bearings in places that the 208 used needle bearings.
 

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