Transmission fluid in radiator

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ironworker96

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Sulphur la
Ram Year
2015
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Hemi 5.7
Got underneath to change oil in my 2015 1500 and noticed reddish liquid dripping from radiator hose Called a buddy up with more knowledge than I and he said it could possibly be transmission fluid leaking into my radiator (I haven't found the leak yet) what could cuase this
 

Wild one

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Got underneath to change oil in my 2015 1500 and noticed reddish liquid dripping from radiator hose Called a buddy up with more knowledge than I and he said it could possibly be transmission fluid leaking into my radiator (I haven't found the leak yet) what could cuase this
The thermal management unit on the drivers side of the transmission would be the only way to get transmission fluid into the coolant. It's the only place the 2 fluids get close together. Coolant is fed into the two hose barbs at the top,and transmission fluid is routed through the 2 bottom holes. If it's leaking internally,you'll also want to probably change your transmission fluid ASAP
 

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Wild one

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Okay appreciate the help, Wild one. I will get up with a shop this week to be looked at
If by chance you do have coolant in the transmission fluid,i wouldn't even start it,i'd have it towed to the shop.
Not saying you do,but in my opinion i wouldn't chance it, if your trucks a 15,and it's never had the transmission serviced ,it's due for a transmission service.
ZF says to service the transmission between 80,000 and 130,000 "kilometers" (50,000 to 80,000 miles) or every 8 years,even if you're not at the milege reconmendations,you're at the age reconmendation.
If you have a shop do the everything,make sure you give them this sheet,and let them know they have to level the transmission pan rail,not the truck.
 

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RonG

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2005
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Cummins 5.9 Diesel
I'm posting this here because of the relevance to the thread topic and in hopes that it might identify some things for others with "Pink Coolant" and/or transmission fluid. I'm also curious as to how the original poster's situation turned out.
I have always found that the more information given on a subject the better others could parse out what is relevant to their own situations. Still, I apologize for this becoming a danged book!

I have a 2005 Ram 3500 5.9 Cummins with 316,000+ miles. The transmission has always been strong in this truck. A couple of years ago I did a little repair inside the tranny to alleviate a "hard to get out of park" issue, but nothing major. I'm embarrassed to say that I have only changed the transmission fluid and filter twice in the nearly 200,000 miles I have put on it since buying it used. But I say this to make the point that sometimes you get lucky... and, you happen to buy "a good'un"!

Two days ago I was about to make a 175 mile trip and just happened to need to make a stop less than 3 miles from home before leaving town.
Well, I may not be real lucky, but I was certainly fortunate, because when I made the stop the truck was IDLING at 1,000rpm. If I had hit the Interstate, I'd likely have gone many miles before realizing the problem; burnt up the engine as well; had to have been towed back; etc.
When I looked at the dash, the temp gauge was almost pegged out. After checking under the hood -- nothing seemed, felt (or smelled) overly hot, at all. It was too warm to attempt opening the radiator cap, so I restarted the truck and turned the a/c off. The temp came down a bit (within the high-side of "ok") so I opened my windows, turned the heat up in the cab and eased back home --- yeah, I know, a real bonehead chance to take. The temp didn't go all the way back up but it didn't really return to normal either. I shut her down as soon as I got home and just let it cool down before doing anything. When I opened the hood and removed the radiator cap, the coolant level was too low to see it, but there was a pinkish "milkshake" stuff visible. Knowing that transmission fluid is the reddest substance to make this change, I pulled the tranny dip stick. Yep, same strawberry shake going on there!
So I did some research and found that what has occurred is that the transmission cooler (located near the starter -- NOT integrated in the radiator as is true of some other makes) has failed/ruptured and corrupted both the trans and the entirety of the cooling system. It is possible that it started as a tiny leak and may have driven many miles with the cross contamination going on.

There seems to be two trains of thought on how to take care of all this:
1. Replace the failed transmission cooler; Completely rebuild, or replace, the transmission; Totally and thoroughly flush the cooling system, replacing ALL rubber (and/or plastic) parts. And I saw a few ideas on "flushing" a cooling system that I've never run across before too! "Powdered dishwashing detergent"?
2. Thoroughly flush both the transmission itself, related components, i.e., torque converter, cooling lines, everything; AND engine cooling system. It was emphasized to be extremely thorough with the flushing, doing everything possible to ensure that all contaminates are removed from each system.

The "Replace it all" folks insist that merely flushing will not get rid of all the contaminates... especially in the trans and converter.
The naysayers of the "just flush" also say that the transmission fluid will eventually render all the engine cooling system rubber (and sometimes even plastic) parts useless and highly likely to result in system failure down the road.

The "Awww, a good flush will do the job'ers" boast that you shouldn't go to all the expense and work right off because, "Hey, what if it works?"

So, at better than 316k miles, I'm aware that I've been riding on borrowed time for a while. I acknowledge that it's truly the right time (in this case) to go ahead and bite that financial bullet and repair the transmission or replace it. I am leaning toward rebuilding it myself. I'm curious what/who others have decided on for the rebuild source(s)? Why did you go with the source? What deciding factors led to your choice? How have your rebuilds turned out over time? I'm aware there are several providers out there that are popular, especially with the "power"/speed happy folks. There are also a lot of much less expensive choices, when it comes to initial costs. How has the "cheap(er)" route panned out for the ones who simply couldn't afford the pricey rebuilds?

This IS my daily driver and I need it up and running as soon as possible, but I really don't want to make a rush decision that I will regret in the near future. I truly would like this to be the last truck I own... unless I can find my original 1959 Chevy Apache. So, I want her done "right" but without going completely crazy with the costs.

I appreciate any thoughts, advice, or even anecdotes in response. I appreciate everyone who contributes to this and all forums of this nature. I believe it is the finest use of the modern communications tools at our fingertips. Thank you all for your time, knowledge, interests, input and introspects.
 
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