Rubicon 241 into non-Rubicon LJ (front driveshaft question)

LincolnJr

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Hey all, I've seen a few discussions around on the topic, but not my specific questions. I'm going to replace the NP231 in my 06 LJ with a NP241 from an 04 Rubicon. I'm also working on a tummy tuck and I already talked to someone at Tom Woods about a custom rear DS at my final length to go from the rear tcase flange to the Dana 44 yoke. But there seems to be a couple of options for the front DS.
1) Custom new DS with 1330 at the tcase and 1310 at the diff end. Pros: simple solution, all new parts, Cons: cost ~$400 and I've read that the 1330 binds more easily than 1310
2) Swap the front yoke on the tcase to 1310 and keep current DS (but I should do new u-joints). Pros: cost for the 1310 yoke and all ujoints/centering yoke = ~$200, Cons: extra work (though I don't mind a side project)
3) any other options I should consider?
 
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A littler tougher to do in this instance since his double cardan is 1310 so he would have to change the ball flange and possibly the Hyoke as well. If he had the Rubicon shaft then running it with the combo joint at the diff would be the way to go.

Yep, thinking with 1/2 a brain again. The 5-134x works on the back, but not the front! :cautious:
 
I expect Denny's would have one. I see they have a 1310 yoke for the 241 but pretty sure it's for the rear and I don't know if they're the same spline count. https://www.dennysdriveshaft.com/

Advance Adapters is another likely source. https://www.advanceadapters.com/

I'd call them both, their websites aren't always clear on some things like that.
 
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I did this exact swap and just used a 1310 yoke. I used one from jb conversions. Something to keep in mind is a lot of the yokes out there are for the jk version of the 241. You need the tj version.

The difference is an o ring in the yoke for the jk and a rubber star washer for the tj.
 
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I did this exact swap and just used a 1310 yoke. I used one from jb conversions. Something to keep in mind is a lot of the yokes out there are for the jk version of the 241. You need the tj version.

The difference is an o ring in the yoke for the jk and a rubber star washer for the tj.

I noticed that. The Nitro Gear part number I think is right is YOKNP241OR1310-32, but it looks exactly the same as other sites that list the same part number with "FSJK" at the end, which is clearly for a JK. I'm going to call a couple of shops like Jerry recommended just to make sure I get the right part.
 
I noticed that. The Nitro Gear part number I think is right is YOKNP241OR1310-32, but it looks exactly the same as other sites that list the same part number with "FSJK" at the end, which is clearly for a JK. I'm going to call a couple of shops like Jerry recommended just to make sure I get the right part.

Yeah this jb conversions photos shows the difference as well and is a link to a yolk with the jk style seal. https://www.jbconversions.com/products/yokes_flanges/1973.php


I believe this is the one I used, 32 spline cv yoke with the front output.
https://www.jbconversions.com/products/yokes_flanges/1942.php

You could use this one as well that they make for the rear. It had the counter bore for the speedo ring that only the tj 241or has. It says compatible for the front output too but I don't think the counter bore is needed on the front. It is $50 more, same yoke other than the counter bore.

https://www.jbconversions.com/products/yokes_flanges/1971.php
 
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I have JK 1350 flange yokes on my 241. Glob of silicon under the nut and it’s good to go.
 
Yeah this jb conversions photos shows the difference as well and is a link to a yolk with the jk style seal. https://www.jbconversions.com/products/yokes_flanges/1973.php


I believe this is the one I used, 32 spline cv yoke with the front output.
https://www.jbconversions.com/products/yokes_flanges/1942.php

You could use this one as well that they make for the rear. It had the counter bore for the speedo ring that only the tj 241or has. It says compatible for the front output too but I don't think the counter bore is needed on the front. It is $50 more, same yoke other than the counter bore.

https://www.jbconversions.com/products/yokes_flanges/1971.php

Very helpful, thanks! I'll keep the rear option in mind, too, but so far I'm planning to just keep the flange and get the Tom Woods driveshaft built to match.
 
Very helpful, thanks! I'll keep the rear option in mind, too, but so far I'm planning to just keep the flange and get the Tom Woods driveshaft built to match.

How many miles on your current driveshaft? Any play in the slip? Getting a new tom woods like you plan really is the best option long term.
 
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How many miles on your current driveshaft? Any play in the slip? Getting a new tom woods like you plan really is the best option long term.

Good question. 153k miles. Definitely getting a new rear DS, because of my 4"lift and I need a DC style. I will check for play in the front shaft slip. If it's good, I'll stick with just replacing the u joints.
 
Very helpful, thanks! I'll keep the rear option in mind, too, but so far I'm planning to just keep the flange and get the Tom Woods driveshaft built to match.

I didn't mean to imply to use that one on the rear. Just that it is one they sell for the rear output that can fit the front. Coincidentally I did use one on the rear since my case didn't come a stock flange. I finally found a stock flange on ebay from a salvage company. I plan on replacing my rear output soon with the stock flange and a Tom woods drive shaft.
 
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Yokes for TC from Northern Drive Train :

Need another yoke for the Rubi transfer case 3104-322CV. Going to go with cutting down a front DS from a TJ in the rear.

Northerndrivetrain.com
Quantity in Basket: 1
Code: PTI-3104-322CV
Price: $48.82 (now $50.23)

Dimension that Shawn is referencing is 1.943 on this part, but NDT says it is on "Backorder" and the Neapco is $105
 
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I agree that swapping the yoke on the transfer case is the best option. The tricky thing about the yoke you need is that it has a different seal surface than most 32 spline yokes. It will need a 1.939-1.949 seal surface, depending on whose specs you are using. Most 32 spline 1310 yokes you'll find will have a 1.875" seal surface, this is the wrong yoke, don't get that one. 1.949 is what you need. We have this yoke for $95 https://4xshaft.com/products/26-spl...1&_sid=06f0512f5&_ss=r&variant=44133909528894. You'll have to select 32 spline for 241 transfer case, 1310, and CV from the dropdown menus. You can also find the yoke from many places if you look for it as a JK yoke. Same yoke fits a JK transfer case. Neapco part number n2-4-jk03 will get you what you need. Spicer makes one as well but I'm pretty sure theirs uses a metal shield to achieve the proper seal surface diameter. I don't like the shield, sometimes they split/crack which causes fluid to leak from the transfer case.
 
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