06 4.0 42RLE going into high temp mode

nubueloce

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Oklahoma
I'm sure this is already been asked, but, on my 2006 Wrangler 4.0 with an auto transmission. Transmission is going into high temp mode and shifting rough. ECM / TCM has been sent to SIA and they said there must be a short. Local transmission shop said the same. Wondering if I need to pull the loom off of all of the wiring or if someone here has had the the same issue. Wondering if it's a sensor or the solenoid. Thanks for the help. Will hook up the OBD and check codes.
 
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I'm sure this is already been asked, but, on my 2006 Wrangler 4.0 with an auto transmission. Transmission is going into high temp mode and shifting rough. ECM / TCM has been sent to SIA and they said there must be a short. Local transmission shop said the same. Wondering if I need to pull the loom off of all of the wiring or if someone here has had the the same issue. Wondering if it's a sensor or the solenoid. Thanks for the help. Will hook up the OBD and check codes.

Mine went into limp mode, with the encouragement of @Jerry Bransford and @AndyG I went over my harness and found a rubbed wire, the loom was crumbling apart and let it rub on the sensor.
20240608_142303.webp


It's hard to see in the Pic but I used liquid electrical tape and new fabric tape and new loom. No problem since the repair.
 
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Mine went into limp mode, with the encouragement of @Jerry Bransford and @AndyG I went over my harness and found a rubbed wire, the loom was crumbling apart and let it rub on the sensor.
View attachment 556519

It's hard to see in the Pic but I used liquid electrical tape and new fabric tape and new loom. No problem since the repair.

That is good place to start! Thanks for the response and I will check in the morning! Hopefully I'll have your luck! 🍻
 
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That is good place to start! Thanks for the response and I will check in the morning! Hopefully I'll have your luck! 🍻

Take your time and go slow. I overlooked mine twice. I found it by gently sliding my fingers over each wire.
 
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I'm sure this is already been asked, but, on my 2006 Wrangler 4.0 with an auto transmission. Transmission is going into high temp mode and shifting rough. ECM / TCM has been sent to SIA and they said there must be a short. Local transmission shop said the same. Wondering if I need to pull the loom off of all of the wiring or if someone here has had the the same issue. Wondering if it's a sensor or the solenoid. Thanks for the help. Will hook up the OBD and check codes.

If you don't already have one, install a temp. gauge.
Then you'll find out you need an auxiliary cooler too. ;)
 
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If you don't already have one, install a temp. gauge.
Then you'll find out you need an auxiliary cooler too. ;)

Yeah I want to put one on as far as the temp gauge goes. As far as the auxillary cooler, I'm 4th generation at a local radiator shop and when I built my all metal radiator I put a 7 plate gm cooler in the radiator. But, will think about an auxillary cooler to go in front and still utilize the internal cooler too.
 
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You’ve really got a multitude of challenges right out of the hole-

And you’re not alone.

Everybody that has one of these needs to take the condition of the wiring seriously- If for no other reason than just the heat.

The fluid that these use is thin. That’s just an unavoidable part of the formula.

The overdrive final drive is dismal and if you are bone stock it is pushed and will run warm.

It is almost as if these things are designed to run hot .....I think the real truth is that they are certainly not designed for the tire set up most jeep owners prefer. The 42 is a good transmission in some respects but yet it has some witnesses and it is not perfectly designed for the jeep TJ platform- It is barely sufficient for a stock rig and so many jeep owners tend to go far away from stock.


If you have larger tires and stock gears it will run even warmer.

If you run it in overdrive when you don’t need to you’re adding to all of that.

Transmission filters do not get changed at the interval that they should and they become inefficient and that will also create more heat on top of all.

I’m going to lay out what I think is your more optimum automatic transmission formula and anything approaching that is probably going to be in your favor-

1. Service the transmission. At least change the fluid in the pan and install a new filter.

2. Gear the jeep correctly for the tires.

3. Install an aftermarket cooler.

4. Learn when to use and when not to use the overdrive. This is even more important if you’re not geared properly. If you’re going to run 33’s with 4:10 gears at least help yourself a little bit.

5. Carefully check your harness and make sure it is in top shape and properly secured so it will stay that way.

6. A transmission temperature gauge won’t hurt- In my opinion if you can’t do everything then that means the more you need to do the gauge so that you can stay out of trouble.

7. Regardless of what people tell you, Be respectful of the capability of the transmission. Don’t let it roll backwards in reverse and slam it in drive. You don’t have to baby it but you can make it last longer by the way you treat it.

Heat is the enemy of automatic transmissions.
 
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This is attention to detail. I bet the majority of people would have missed this.

Or just me bound and determined not to drop the valve body :ROFLMAO: :ROFLMAO: :ROFLMAO:

I really want to thank @AndyG for the encouragement to go over the harness first!!!!! It's not easy with the transmission still in the Jeep but with determination it can be done.
 
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