Will an Atlas 5.1 transfer case fit in my JKU?

Henson

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Mar 24, 2020
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Hi I have a 2015 JKU with an automatic I’m running Dyna track 60s with 40 inch tires With 538 gears I would like to put an atlas 5.1 transfer case in it looking to see if anybody has any ideas if it would work or has somebody done it thank you Tim
 
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Henson

Henson

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Mar 24, 2020
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They told me i can’t get the two speed low you can only get high and low For my 2015 JK you It has an automatic in it Thank you so much..Tim
 

Chris

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Last I spoke with Advanced Adapters they had told me that while the transfer case will fit, it won't work with the 2012+ JKs with automatic transmissions due to issues with the stock PCM not knowing how to handle it being there (or something like that).

Of course I can't believe that someone wouldn't have figured out a work around to that.
 
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Henson

Henson

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Mar 24, 2020
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Thanks Chris yes I sent my PCM unit and had an unlocked so I could reprogram the 15 for the tires in my gears I don’t know if the transfer case go that low on my controller I didn’t think about that scratching my head on this 😀
 

The shuggs

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Oct 24, 2019
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Edmonton, AB
My guess as to why the programming can't be change to solve the issue is because you would need to add new code to account for multiple TC gear ratios, rather than just changing parameters. Instead of just going in and changing a number from 2.72 to 4.0, you'd need to add logic loops. The current programming probably is checking the output speed of the TC against engine rpm, transmission gear, and whether the TC is in low range or not. A fix would need to have sensors to know which TC ratio you're in, as well as new lines of code to verify the TC output against the sensor reading. The extra code would require more testing than most manufacturers are willing to put in.