2012 JKU Rubicon Build/Adventure Thread

[Comanche Scott]

Congrats on getting it back. :beer:

That heating thing is a strange deal.
I pulled a 3,500lbs Scout 4x4 as a toad behind the JK, and it would hit 220*F on long hard hills, but that was it.
Same engine and drivetrain, so there has to be something else. I do have the HR hood with the vents opened up.

Do you have time to pull out one of the inner fender liners to see if extra venting would stop the issue? Just as a test. If it worked, you could always add a couple of louvered panels to the stock liners, or replace them with aftermarket.
I get that Jeep should be able to fix this, but sometimes, they just don't have the ability to do what we can do ourselves.

 

[Septu]

Congrats on getting it back. :beer:

That heating thing is a strange deal.
I pulled a 3,500lbs Scout 4x4 as a toad behind the JK, and it would hit 220*F on long hard hills, but that was it.
Same engine and drivetrain, so there has to be something else. I do have the HR hood with the vents opened up.

Do you have time to pull out one of the inner fender liners to see if extra venting would stop the issue? Just as a test. If it worked, you could always add a couple of louvered panels to the stock liners, or replace them with aftermarket.
I get that Jeep should be able to fix this, but sometimes, they just don't have the ability to do what we can do ourselves.

I had the inner fender liners out a couple years ago when I did a trip to Edmonton - them out made it a LOT worse. Putting them back in made an extremely noticeable difference. Towing my little 1300/1400 lb trailer in the mountains I couldn't get the temps below 230/240. They'd go up and just wouldn't come down. I redlined the gauge going up one mountain pass. On the flats around Edmonton just on the highway my temps were over 230 just doing highway speeds (110 kph there). Since putting them back in, the only time I've come close to redlining it is in some deep snow that we were digging though with some pretty high revs.

Jeep has finally washed their hands of this. According to them everything under the red line is "normal" and unless something significant happens or changes, they will not investigate this any more. Which while extremely unfortunate, is understandable. My local dealer spent a lot of time investigating my complaints and as they didn't "fix" anything, I don't think they were paid for their time.

I think my next step is just finding someone who can change the programming for when the fan kicks into high. It's either that or keep throwing money at the cooling setup (or just going to a different engine completely).

 

[Comanche Scott]

Hope the fan change works. If the fans were disconnected, and run through their own thermostat would it trigger an MIL?
If not it might be worth a try to test your theory, before paying someone to reprogram (if that is even possible with the stock PCM).

B.J. had an AEV conversion with the 5.7L, he noted the only thing he didn't like was the heating issues. If I remember correctly, his new AEV JK has the 6.4L VVT, and doesn't have the heating issue.
So, as a "money is no object" upgrade, that could be a pretty cool way to "fix" the overheat issue.

 

[Septu]

Hope the fan change works. If the fans were disconnected, and run through their own thermostat would it trigger an MIL?
If not it might be worth a try to test your theory, before paying someone to reprogram (if that is even possible with the stock PCM).

B.J. had an AEV conversion with the 5.7L, he noted the only thing he didn't like was the heating issues. If I remember correctly, his new AEV JK has the 6.4L VVT, and doesn't have the heating issue.
So, as a "money is no object" upgrade, that could be a pretty cool way to "fix" the overheat issue.

Until I win the lottery... unfortunately I don't fall into that zone. Besides, that's like a 20k upgrade. :eek Unless I blow up the engine, the odds of me going there any time soon are pretty remote. Mind you considering what I'm going to end up spending for my 2 week vacation in FL/TX... perhaps it's not that much of a stretch after all lol. I mean I'd be over 1/4 of the way there!

Yeah there was someone else on one of the boards (JKF?) who said he dumped 20k into trying to resolve the issue. He eventually did with a custom rad. That seems extremely excessive and I'm honestly not all that interested in experimenting to that degree. I do know that the PCM settings for the fan can be changed very easily if one has the right software. I don't think it would cost that much (maybe a couple hundred) if I could find someone with the software to do it. Not sure Whitehorse is big enough to have someone with this s/w. It might just be something that I arrange to do next time I go south (likely next summer).

 

[Dan Grec]

I do know that the PCM settings for the fan can be changed very easily if one has the right software. I don't think it would cost that much (maybe a couple hundred) if I could find someone with the software to do it. Not sure Whitehorse is big enough to have someone with this s/w. It might just be something that I arrange to do next time I go south (likely next summer).

I looked into this when I was doing my diesel swap.

It can absolutely be done with programmers that you can buy for yourself, though it's not something the programmers for a couple of hundred can do (they usually only modify the TIPM).
It's more like 600-800 to get one that can modify the PCM.

As a different option, there is also a place on the East Coast (I wanna say New Jersey) where you can send your PCM and they'll do all kinds of cool stuff to it (They were going to delete the o2 sensors, etc. out of mine so the check engine light would go off)
It's who Bruiser send the PCM to when they do diesel conversions.

Let me know, I can see if I can dig up the name of the programmers and the company.

-Dan

 

[Septu]

Thanks Dan. I might take you up on that if I'm unable to find someone out west who can do this while I'm there. But I'm honestly not in a rush. Chrysler has given me paperwork in writing that states that everything under the red line is considered "normal" and that unless I hit the red line I do not need to change/adjust anything.

Who knows... maybe I'll blow up this engine before my 3 years/100,000k is up.

 

[Septu]

Well found out the hard way that a 4 year and 11 month old battery doesn't like -35c temps. And especially when not plugged in. Decided not to start today. Called BCAA (love that subscription) and had them give me a boost. 90 minutes later I turned it off and tried to start it again... no dice. Fortunately I was at work and borrowed the booster pack. Then went shopping for batteries. Grabbed a Motomaster 760 CCA battery (the biggest one they have). Unfortunately I had to change it outside in the cold and wind. That sucked.

But almost 5 years out of the stock 475 CCA battery after draining it completely at least 3 times (that I remember) isn't too shabby at all.