Transfer case anyone do a DIY swap?

Jeepjunkie

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I know someone here has swapped transfer cases. Is it a reasonable DIY for someone who can turn a wrench? I do most of my own work, except gears.
I’m considering an atlas or a rubicon t-case for my sport. I had blast wheelin’ today, but could have used lower gearing on some technical sections. My rig is already modded (regeared, lifted, PR44, etc), so t-case or a rear locker (already have a front locker) are next.





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Billet_JLU

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I’m interested in people’s feedback. I have a rubicon tcase in the corner of the garage just waiting on the time to be able to install it.
 

MadDog27

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Wanted to follow up on this? Has anyone done it? I’m assuming it’s pretty straight forward and just unbolt and swap.

Does anyone know if there is a difference between a manual tcase and an auto tcase? I’d like to swap mine out to the rubi 4:1 tcase but want to make sure I get the right one.
 

Billet_JLU

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Wanted to follow up on this? Has anyone done it? I’m assuming it’s pretty straight forward and just unbolt and swap.

Does anyone know if there is a difference between a manual tcase and an auto tcase? I’d like to swap mine out to the rubi 4:1 tcase but want to make sure I get the right one.
I believe theirs a difference between auto and manual.
 

MadDog27

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I believe theirs a difference between auto and manual.
Alrighty. Wonder what the difference is? Shafts length? Wonder if whatever is different, if it can be swapped with the tcase going out or if it’s a major difference.
 

Billet_JLU

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Alrighty. Wonder what the difference is? Shafts length? Wonder if whatever is different, if it can be swapped with the tcase going out or if it’s a major difference.
I’m not sure but I think I’ve read on here it’s a difference in the spline count.
 

D60

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T-case R&R is pretty straightforward wrenching. Basically, driveshafts, any skids or crossmembers that are in the way, shift linkage, watch the breather, disconnect electrical plug(s) and then unbolt from tailshaft housing. Slide back off tailshaft and don't drop it or crush yourself.

I'd be really surprised if there was a difference from auto to manual but I've never researched the JL. I can't fathom a reason FCA would do that but I can't understand a lot of what FCA does. Typically spline counts vary at the engine to transmission. In the past GM has used no less than three different bolt patterns and spline counts from trans to t-case, so maybe (makes trying to assemble a GM doubler a PITA). OTOH Ford used a round 6-bolt pattern and 31 spline tailshaft for 30+ years.
 

MadDog27

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T-case R&R is pretty straightforward wrenching. Basically, driveshafts, any skids or crossmembers that are in the way, shift linkage, watch the breather, disconnect electrical plug(s) and then unbolt from tailshaft housing. Slide back off tailshaft and don't drop it or crush yourself.

I'd be really surprised if there was a difference from auto to manual but I've never researched the JL. I can't fathom a reason FCA would do that but I can't understand a lot of what FCA does. Typically spline counts vary at the engine to transmission. In the past GM has used no less than three different bolt patterns and spline counts from trans to t-case, so maybe (makes trying to assemble a GM doubler a PITA). OTOH Ford used a round 6-bolt pattern and 31 spline tailshaft for 30+ years.
Awesome post. Thanks for the heads up on some of that. Been doing some asking around and I Am hearing they are the same between auto and manual as far as the T-cases go.
 

Billet_JLU

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Awesome post. Thanks for the heads up on some of that. Been doing some asking around and I Am hearing they are the same between auto and manual as far as the T-cases go.
If they are the same I paid more for a manual t case than what an auto t case was selling for.
 

Billet_JLU

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Auto transfer case part number: 68240441AA
Manual transfer case part number: 68321888AA

With different part numbers I would think something is different but I'm not sure.
 

MadDog27

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Interesting. Again, I’m hearing different stories depending on who you ask. I wonder what makes them different then and if they are, can you swap parts from the old case to make the new one work.
 

sdrawz

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I suspect the auto and manual T-cases are different in the input shaft. The JK's were like this as well. To the point of one being female and the other male. If you find the correct case, should be very straight forward as a swap. You will need to edit the ECM/PCM to say 4.1 case vs 2.71. I assume Tazer JL can do that..??
 

FilthyJLU

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I suspect the auto and manual T-cases are different in the input shaft. The JK's were like this as well. To the point of one being female and the other male. If you find the correct case, should be very straight forward as a swap. You will need to edit the ECM/PCM to say 4.1 case vs 2.71. I assume Tazer JL can do that..??
Yes, I’m pretty it’s just a correct transfer case and the Tazer
 

Billet_JLU

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Have you had any luck doing the swap?
No I haven’t done the swap yet. This is something I need to add to the list of things to get done.
 

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