I'm sure your dealer knows what they're doing, but obviously if some of us have changed the internals correctly to adjust for different tires sizes with a Procal on Pentastar engines with new transmissions then the other computer logic routine - the gear sizes - is the part that changed. After retiring with 38 years in the computer industry, as a Plan B for now, I'd calculate the difference between the gear ratios, then equate that back to a hypothetical change in tire size, program in that change, and be done with it. It's certainly worth a try.

 

Warning: Changing gears on a 2012 JK will cause it to go into limp mode.
2012 JK Wranglers now include the A580 transmission. With this new trans comes a new trans controller, and unfortunately this controller is programmed to put the vehicle into limp mode if it senses a change in gear ratio. Even a Jeep dealer cannot override this.
AEV has a fix for this and we are currently working on integrating it into our ProCal Module. In the meantime, we recommend that you hold off on changing the gears in any 2012s. We expect ProCals with the updated code to be available by the end of September.

 

I was going to post the same. AEV stated this earlier in the week the current ProCals ant help with the limp mode experienced when regearing a 2012.

My guess is the old ProCals will be eligible to be updated to the new coding once available. AEV has been great with regard to customer service so I would be surprised if someone was left high and dry.

 

I take it you work for Aev then. Does the procal work fully with 2011 jks?

 

Yes it does mine works perfectly with my 2011.

 

Someone else asked this on another board but I didn't see an answer, the Procal will fix this but what happens when you need to return everything to stock mode for a trip to the dealer? Will you be stuck in limp mode then?

 

Does anyone put gears back in just to go to the dealer??

 

I'm referring to returning the computer settings back to stock, not the gears.

 

I was at the dealer when I pick up my 2012. There was a guy who had a 2012 regeared at the dealer with 5.13. I told him about the problem, He said They had no problem with this limp mode.

 

2012 Rubicon 6 speed manual 4.10 with 35's KM'2s = Perfect! (IMO)