I just pulled the trigger on re-gearing my 2012 JK. I went with Nitro Gears 4.88 running on 35"s. The shop I used told me I needed to use the AEV ProCal Module to re-calibrate the computer to compensate for the new gearing. I am just breaking in the gears by normal street driving for the first 300 miles. I am about 150 miles in and having a problem.

Several times now.. the check engine light comes on and the Jeep wont shift into high gear and the tiptronics stop working. When I turn the engine off and re-start, it works again...

When I plug the AEV ProCal module in... the check engine light turns off.

Anyone run into these issues after re-gearing??

 

yes. you have to calibrate the computer when you change gears or tire size

 

Isn't it more probable to have issues with the newer trans and changing gears workout letting the computer know? I believe that's why/ when the jeep jumps to limp mode.

 

I think so too! Believe it has to be something with the computer. The only thing that is strange is that it seems to happen at about 20 min into driving it(when it warms up).. once a shut it off and re-start it works again??

Taking it back to the shop where I had the re-gearing done tomorrow.

 

That is limp mode that you are experiencing. A restart always resets it. In the 2011 and up, if proper gears and tire size are not reprogrammed in it will continually go into limp mode.

 

Thanks Jeff. OK, than it sounds like the AEV ProCal is not program correctly or not working.

 

I too am having the same problems in my 2018 JKU, my 35' tires are worn down, and i just had my 4.88 gears installed. i have sent it back to my mechanic three times now and keeps coming back with the same issue. also i am locked which im not sure if that is an issue with the gears, but when i turn sharp or stop and go stop and go my jeep goes into limp mode where it will not shift up or down from third gear. when i put it in park i can hear a ticking noise. after i shut it off and restart the noise is gone and the jeep runs great for a little while. evern my mechanic at the dealership doesn't know what to do. ive called super chips, they said the update went great and my jeep took it just fine. does anyone else have any other idea how to perm fix this issue or why it is continuing to do this?

 

First, where are you in Texas? Who did your regear? The most obvious question is did you program the new gears? I presume so since you not calling superchips. Have you scanned this jeep with something that can read into the individual modules like Jscan app or BlueDriver (or any other)? if you're going in to limp mode, there's going to be some code in the transmission module.

 

yes i have re programmed the computer, set everything back to stock and reprogrammed again. my mechanic has flashed the computer twice now. so after more reading into it, it does make sense that the speed sensors would put a damper on the rear being locked. its not the gears that did it, it was the true locker that is making the issue persist. i have to take the true locker out and replace it an electric locker or air locker. cant have it locked in 2 high without the computer throwing codes.

 

Hey did you ever solve your issue whit Jeep having the same problem 488 and lockers