Looks to be another WranglerFix.com thread (haven't received the PCM yet, its coming)

T Crawford

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Well I was hoping this was one of this- it won't happen to me things and I've been ignoring it but I've had a nagging feeling about some of things my jeep has been doing in the last several months.

I have a 2006 LJ Rubicon that I bought new at a Oregon dealers in April of 2007 when Jeep offered 6 years 0% financing, I had just purchased a TJ that had 100K from a Fort Lewis solder with plans to play with it when I saw the 0% offering, I'd always wanted a Rubicon LJ, but couldn't bring myself to spend the money. I traded the TJ for the LJ and didn't look back- I took it home and got a few goodies installed on it then got married and had two kids. Fast forward to today- its got 35K on and the same toys I installed 12 years back, but I recently added remote start, heated seats and power locks/windows- gotta have the creature comforts.

Now to the issues earlier this summer I was in the Lava Hot Springs area of Idaho doing a short trail ride with the kids- it wasn't more than 75 out and the rig start to run around 215- its never done that before and I'd changed the coolant recently, now in the last few weeks I've had a check engine light come on for an O2 sensor (so I ordered some new NGK, they are still in the box in the garage), I reset the light it went away. But then I have had a few random hard shifts between 1 and 2nd- not enough to bother me but enough to make me think about it.. Then the kicker- this last week I started to go down my street pulled to the side to stop and adjust something put it back in gear and hit the gas- it just reved, I stopped put the brake on and hit the gas again and off we went. (CRAP)

So I shot a quick query out to Mark - if you've dealt with him you know he answers the phone most of the time and calls back real quick- he confirmed what I hoped not and figured I'd better get one ordered- that was Monday- today he tells me it will probably ship tomorrow and I should get it soon after that, we had a short chat with a a few options he had and I opted for something new that hes been talking about-

So hopefully in a few days- I'll get my new PCM and the adjustments that Mark and his team had made to it and I'll be a super happy camper, not so happy about the budget but thats life (yeah the kid threw something a the flat panel TV and the 2 year old TV met its demise- that was hard on the budget too)

I'll reply back to the thread when I get my new parts and get a bit of time to install it- the damn jeep stalled again today going over to the hardware store to get some stuff for my KL-
 
Mark is a great guy, the best-of-the-best as far as customer service and taking care of his clients needs goes.

I look forward to hearing your follow-up.
 
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Well tried driving the jeep yesterday- the transmission is actually worse- put it in gear and it wouldn't go anywhere- so the computer is really needed at this point- things went south quickly this week.
 
you mentioned that there was a rise in temp. then a few days later the trans went. Maybe check the coolant to see if the trans cooler is leaking.

i would also check trans fluid before assuming is the pcm

what coolant did you use? If you mix the oem Chrysler with green coolant it could cause problems.
 
The transmission iss I believe is separate from the overheating I didn’t ket the temp get into the red zone before I did things to cool it down ,tuned off the ac, turned the heat on high then shut it down for a hike.



I used the correct Mopar premixed oem coolant. The transmission has gotten worse this week and the cooling issue was in July.

I’d also had the transmission serviced at a local independent shop who dropped the pan and changed the filter
 
The oem trans cooler goes throught the bottom of the radiator, when they break and leak, they make a milk like mix when coolant and trans fluid mix.

what engine codes did you get? I would also replace the sensors you mentioned before replacing the pcm.
 
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We need a "Wrangler- fixed" thread for Mark of only testimonials.

We hear this so frequently.

And to be fair, he's in a tricky line of work- there is a lot going on electronically with all modern vehicles, and a lot of TJs see too much water and neglect , so he may occasionally get into something he didn't ask for , all just trying to help.

That said, his discernment of the symptoms and recommendations fix a lot of TJs. He doesn't try to just push PCMs to solve everything- he sells PCMs to owners who's TJ's show symptoms indicative of PCM failures, and he basically nails it.
 
To be fair I may go back and try my factory pcm at some point but there is ebnough data in my mind to show an issue with these years, I have heard poor feedback about a few of the other vendors but at $600 this price is good and I’m willing to risk it. For just the money aspect, it a piece of mind
 
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To be fair I may go back and try my factory pcm at some point but there is ebnough data in my mind to show an issue with these years, I have heard poor feedback about a few of the other vendors but at $600 this price is good and I’m willing to risk it. For just the money aspect, it a piece of mind
If it doesn't act up, I'd never reinstall it...I think they can damage other things. $600 is nothing , half the cost of nice 33" tires you start wearing the second you back off the rack. And honestly, on a 14-16 year old anything....any vehicle ...$600 invested is nothing. Seriously. 45-50 bucks a year.
 
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what coolant did you use? If you mix the oem Chrysler with green coolant it could cause problems.

OEM coolant is ethylene glycol coolant with HOAT technology to reduce corrosion and extend service life.

Ordinary green coolant is also ethylene glycol coolant but without the HOAT additive package.

They can be mixed without issue. All that happens is that any long life characteristics are reduced to the life of ordinary ethylene glycol coolant, about 3 years, and it won't have the same anti-corrosion additives that give the OEM and aftermarket replacements such as Zerex G05 their long life properties.

It will have zero effect on a transmission unless there is a leak and coolant and ATF have mixed. The pink Strawberry Milkshake of Death that results is a disaster no matter what type of coolant or what type of ATF, but the chemical compositions of automotive coolant and ATF have nothing to do with the cause of such leaks.
 
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It will have zero effect on a transmission unless there is a leak and coolant and ATF have mixed. The pink Strawberry Milkshake of Death that results is a disaster no matter what type of coolant or what type of ATF, but the chemical compositions of automotive coolant and ATF have nothing to do with the cause of such leaks.
thats what im refering too, the strawberry thing, dint remember the name. my guess is that when the trans cooler breaks inside the radiator the engine temp could go up a bit due to the trans fluid temperature. That could also explain the shifting issue.
 
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I used the factory host premix “Mopar brand”. No concerns then, I’m in the process of servicing the transmission now due to a leaky pan seal, I going to rtv, vs the gasket that the last shop did. Fluid actually looks good and it was almost 2 years ago. It I’m doing it again. UPS and the holidays means slow delivery