42RLE transmission overheating

Another update. I got my car back and got the new lines in. Worked great for about a day then I had to drive about an hour away and as soon as I got into slow traffic I felt a kick while I was stopped and then the Jeep wouldn’t accelerate like it should (it hesitated but the Rpms went up) and wouldn’t shift gears. So it’s doing the exact same thing it was doing before. I let it sit for about an hour then it started to shift again. Any ideas?

Yes, my idea is take it back to the shop.

As much as I'd love to sit here and try to diagnose this, it's absolutely, 100% unacceptable that a shop that was supposed to be fixing the issue has not fixed it. I'd be fuming about now if I were you.
 
Yes, my idea is take it back to the shop.

As much as I'd love to sit here and try to diagnose this, it's absolutely, 100% unacceptable that a shop that was supposed to be fixing the issue has not fixed it. I'd be fuming about now if I were you.
I can give them another shot. This is a different shop that did the work this past time so I’ll have to see. Already put about $4k into this Jeep trying to fix this one problem, no one seems to be able to figure it out. Next option is a Jeep dealer then maybe sell it if they can’t figure it out either.
 
  • Like
Reactions: Chris
Another update. I got my car back and got the new lines in. Worked great for about a day then I had to drive about an hour away and as soon as I got into slow traffic I felt a kick while I was stopped and then the Jeep wouldn’t accelerate like it should (it hesitated but the Rpms went up) and wouldn’t shift gears. So it’s doing the exact same thing it was doing before. I let it sit for about an hour then it started to shift again. Any ideas?
I tried to explain that the lines were not the problem and the second shop was full of shit and you ignored that. Do you believe it now?
 
Any resolution to this problem? I am having a similar one. It seems to happen when it's hot outside and my temp gauge gets a little past 210 but no where near overheating.
 
It's quite possible your problem and the OP's problem is related to the TCM (transmission control module) inside of the PCM. Lots of 42RLE transmission issues in the 2005-6 models are caused by bad programming in the TCM which wasn't always known or understood. I'd give Mark a call at www.wranglerfix.com and talk to him about your problems. They are the first to have come up with a true fix for the TCM by reprogramming it to get rid of the bugs. It just involves swapping your PCM for one from them. The OP's problem was initially diagnosed by his shop as heat related but that was probably a bogus diagnostic. I got my '04 42RLE hot a couple times before installing a cooler but it never experienced those problems.
 
Will these schedules throw a code?
No, those shift schedules reduce the heat generated and get the temperatures back to the regular range. It's part of the normal operation and not something that requires service. I've had mine in overheat several times on the trail, it's obvious, delayed shifts and very early torque converter lockup.
 
No, those shift schedules reduce the heat generated and get the temperatures back to the regular range. It's part of the normal operation and not something that requires service. I've had mine in overheat several times on the trail, it's obvious, delayed shifts and very early torque converter lockup.
What’s the cure. I have this just around town driving as well as some rock crawling
 
What’s the cure. I have this just around town driving as well as some rock crawling
You're thinking the torque converter is locking up on the trail or too soon on the on the road? I've noticed mine seems to lock up more easily if not sooner if I have the Overdrive switched off.
 
What’s the cure. I have this just around town driving as well as some rock crawling
Overheat schedule starts at about 240F. If your transmission isn't around this temperature it's probably not related to the shift schedules. You could have a bad temperature sensor in the transmission but I think that would throw a code.
 
You're thinking the torque converter is locking up on the trail or too soon on the on the road? I've noticed mine seems to lock up more easily if not sooner if I have the Overdrive switched off.
Yes. It locks up too soon. I can put my big toe on the brake gently to unlock it.
It also shifts hard into third on easy acceleration.
Actually shifts great when it’s cold.
 
Yes. It locks up too soon. I can put my big toe on the brake gently to unlock it.
It also shifts hard into third on easy acceleration.
Actually shifts great when it’s cold.
Let's eliminate one easy possible cause of shifting problems. I kinda doubt this is the reason but do it anyway. Start your engine, let it warm up, then while the engine is still running (important!) check the transmission's ATF level with its dipstick. It should be all the way(!) to the full line, if not a little over the full line. The engine must always be running when checking an automatic transmission's ATF level.

If it's low, make sure to add no other type of ATF but ATF+4. If it doesn't say ATF+4 in big letters on the front label it's the wrong stuff.

If the level is ok, I'd take it to Westminster Transmission and talk with Joe. They're located in Westminster in Orange county. They specialize in Jeep transmissions (they prep many King of the Hammers race vehicle transmissions) and they will not overcharge you like many other transmission shops will.
 
  • Like
Reactions: Mobusaki