Transmission Cooler

[mhholbrooks]

Alright, PO765 code been popping up and throws it into Limp Mode. Reset it with my Innova handheld. Sets, reset, sets again. It eventually would be fine and drive. Tired of that plus I just need to fix it. Picture is what came from the trans cooler. Drained the radiator and it looks the same. So, leak inside the radiator and passing back and forth. It’s weird, the fluid doesn’t even look petroleum based. Any other ideas would be greatly appreciated.
Question is, can I delete the cooler for a little bit? I want to drain and flush the radiator, plug the cooler, and a simple run around circuit for the transmission until I can get a new radiator and plumb it back in. Caveats: in Mississippi(hot and humid), no heavy traffic, no A/C and no trailer pulling. It’s my DD. Really just trying to get it back on the road and check the transmission and get time to buy a good radiator and make sure I didn’t screw something up by resetting it.
Thanks for any help!

 

[Moglocker]

Alright, PO765 code been popping up and throws it into Limp Mode. Reset it with my Innova handheld. Sets, reset, sets again. It eventually would be fine and drive. Tired of that plus I just need to fix it. Picture is what came from the trans cooler. Drained the radiator and it looks the same. So, leak inside the radiator and passing back and forth. It’s weird, the fluid doesn’t even look petroleum based. Any other ideas would be greatly appreciated.
Question is, can I delete the cooler for a little bit? I want to drain and flush the radiator, plug the cooler, and a simple run around circuit for the transmission until I can get a new radiator and plumb it back in. Caveats: in Mississippi(hot and humid), no heavy traffic, no A/C and no trailer pulling. It’s my DD. Really just trying to get it back on the road and check the transmission and get time to buy a good radiator and make sure I didn’t screw something up by resetting it.
Thanks for any help!

View attachment 693596

Apple juice,you really need to get a new radiator

 

[mhholbrooks]

Yeah, I know. Just trying to get it back right now. Everybody says stay with Mopar OEM, but those hoarded up ones are like $700 since Mopar discontinued ‘em. Trying to figure out the next reasonable fix.

 

[macleanflood]

There's this...

Thread 'How to install a Derale 20561 transmission cooler on your Wrangler TJ'

Dec 24, 2015

With a recent series of serious overheating incidents while offroading and towing my little pop-up trailer, I decided to hasten my plans to install an auxiliary transmission cooler for my 42RLE automatic transmission. I had added one to my previous TJ that had the more robust 32RH, but Jeep’s newer automatic transmission like my 2004 Rubicon has is far fussier about such things.

High temperatures are the #1 killer of automatic transmissions. So, it makes a lot of sense to make sure it doesn’t overheat while towing trailers, rock crawling, offroading, or just plain crawling in heavy...

• Jerry Bransford
• 32rh 42rle auto tranny derale tranny cooler transmission transmission cooler
• Replies: 298
• Forum: TJ How-to Guides

• 

-Mac

 

[Moglocker]

Yeah, I know. Just trying to get it back right now. Everybody says stay with Mopar OEM, but those hoarded up ones are like $700 since Mopar discontinued ‘em. Trying to figure out the next reasonable fix.

Go get one from O’Reilly,and try to change as much fluid as you can or you will need a new transmission.

 

[mhholbrooks]

Thanks. I’ll give that a look too. I did see another thread with a YouTube video on how to drain and clean out the TC. I’m gonna have to try something before I just give up on this transmission.

 

[Moglocker]

Thanks. I’ll give that a look too. I did see another thread with a YouTube video on how to drain and clean out the TC. I’m gonna have to try something before I just give up on this transmission.

Just put a drain plug in the pan after you get a radiator,and run for a few minutes,drain and repeat a few times,it’s better than doing nothing.

 

[hear]

Thanks. I’ll give that a look too. I did see another thread with a YouTube video on how to drain and clean out the TC. I’m gonna have to try something before I just give up on this transmission.

TC = Torque Converter or Transfer Case

I've never heard of a torque converter being effectively drained. Your best bet is a full flush, which gets most of the bad stuff out but ultimately just really dilutes whatever bad stuff didn't come out in the flush.

If water/coolant spends any time in your transmission, it will break down the glue that holds the friction material to the substrate. You'll feel it slip more and more and eventually need a rebuild.

It's probably too late to take the rad out of the circuit in the name of stopping the bleeding, but I would 100% do that if I was going to drive it still. Heat will also cause your transmission fluid to break down, but this is what I do know: what you currently have circulating through there WILL destroy your frictions. Driving in the near term MAY generate enough heat to do damage. Having a temp gauge would be very handy right now. Actually, it probably will generate enough heat. You're kinda screwed either way if you must keep driving it.

I figure your radiator is also compromised, no? Do you have ATF in your coolant? That's probably a lesser problem than the water in your trans. This is what I would do, probably. YMMV.

1. un-plumb the trans cooler
2. do a trans flush to get that crap out as best you can. Need the engine running for this, so sequencing is important.
3. un-plumb the radiator and do a coolant flush to get that crap out of the water passages
4. replace the radiator
5. Optional, I guess: add a trans cooler, and plumb it in after the rad cooler.
6. Optional, I guess: add a trans temp gauge because it's just good to know what temp your trans is running at if you care about it's life

 

[KennethS]

I want to drain and flush the radiator, plug the cooler, and a simple run around circuit for the transmission until I can get a new radiator and plumb it back in.

That was my thought. Plug the cooler ports, the as in one of the above posts install an external trans cooler. You will have your desired OEM MOPAR radiator and a more efficient trans cooler.

 

[mhholbrooks]

Sorry, didn’t think about that. TC = Torque Converter
Thanks. That’s all good advice. I’ll do it that way, which is kinda how I was gonna do it.
Btw, you asked if there was ATF in the coolant. Both samples look exactly the same. It’s like they’ve completely mixed. When it’s sloshed around in the jars, it won’t stick stick to the side like you’d expect any petroleum product to do.

 

[mhholbrooks]

That was my thought. Plug the cooler ports, the as in one of the above posts install an external trans cooler. You will have your desired OEM MOPAR radiator and a more efficient trans cooler.

That’s a good point because the radiator’s not leaking. I can use this other advice and “try” to flush and hope for the best. Gotta bunch of Life crap happening and trying to put off a trans rebuild.

 

[KennethS]

Years ago the trans cooler in my classic car leaked and it created a lot of gooey stuff in the cooling system. After replacing the trans cooler (copper brass radiator) and many flushes to get it all out of the engine, all was well.

 

[mhholbrooks]

I like you, Kenneth!!
You’re Hopeful! That’s what I’m trying to be with this situation. Otherwise, you just feel Stupid for letting it go so long. With this other great advice and insights and a little bit of Hope, maybe I can pull this thing through.
Thanks!