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Trans Oil Cooler leaking

Green Line Lawn

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my trans, engine oil cooler is leaking (see pictures), has anyone had any success or recommendations in separating trans and engine oil and running cheaper (aftermarket) external oil coolers? just seems like a cheaper (maybe better option).
would appreciate any suggestions with this..
 

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TOBASH

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my trans, engine oil cooler is leaking (see pictures), has anyone had any success or recommendations in separating trans and engine oil and running cheaper (aftermarket) external oil coolers? just seems like a cheaper (maybe better option).
would appreciate any suggestions with this..
Which is leaking? My Project Joshua M1165 thread discussed bypassing the engine oil cooler and will later show my new aftermarket unit.

Long story short, I had a 24” hose made to accept the oil cooler hose fittings. I then coiled the hose and stuffed it out of the way. Leak is bypassed and gone. Later I will have fittings added to oil and tranny and power steering replacement coolers on a custom made angle iron support.

In all fairness, this was HummerH1 Eric’s idea. He has been running something like this for just under 300K miles.

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Green Line Lawn

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Which is leaking? My Project Joshua M1165 thread discussed bypassing the engine oil cooler and will later show my new aftermarket unit.

Long story short, I had a 24” hose made to accept the oil cooler hose fittings. I then coiled the hose and stuffed it out of the way. Leak is bypassed and gone. Later I will have fittings added to oil and tranny and power steering replacement coolers on a custom made angle iron support.

In all fairness, this was HummerH1 Eric’s idea. He has been running something like this for just under 300K miles.

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thanks for your reply. the leak is the side coil of the trans cooler part. apparently humvees have a dual purpose radiator / cooler that is split into engine oil and trans oil cooler. my question is why i cant i take that cooler out and install 2 separate external coolers (one for engine oil and one for trans oil) and mount them somewhere under the hood. Universal external coolers run under $100 each, plus some hoses, where a replacement humvee oil cooler is $1k. cant find any posts or information of someone else doing it, so was inquiring why not?
 

TOBASH

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thanks for your reply. the leak is the side coil of the trans cooler part. apparently humvees have a dual purpose radiator / cooler that is split into engine oil and trans oil cooler. my question is why i cant i take that cooler out and install 2 separate external coolers (one for engine oil and one for trans oil) and mount them somewhere under the hood. Universal external coolers run under $100 each, plus some hoses, where a replacement humvee oil cooler is $1k. cant find any posts or information of someone else doing it, so was inquiring why not?

Later years have coolers for engine oil, tranny fluid, and power steering fluid. Older years have a separate power steering cooler with a combination engine oil and tranny fluid cooler.

I am splitting into three aftermarket units eventually. Power steering and tranny are low pressure. Engine oil cooler should be able to withstand 80 PSI (as our vehicles probably top out at 60PSI).

Military vehicles need to withstand desert heat driving 60MPH weighing 24k lbs.

My vehicle will never weigh that much, so things won't strain and heat up the same way. And when I go to Death Valley, I won't be driving at 60MPH. The $1000 combination engine oil/tranny fluid/power steering fluid cooler is overkill for my application BUT AMG needed to manufacture one cookie cutter base model for all applications, meaning that they all were given over the top cooling units. Unnecessary in cooler climates BUT totally needed by 24,000 lb. units in desert warfare.

You do what you feel comfortable with, but I am building a triple cooler bypass for less than $350. I have the parts and will do this after I finish sorting out the transmission.
 
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TOBASH

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man…those pesty engineers who designed all this stuff….who Would Have known you didn’t need any of it…LOL
HummerH1 has run without coolers for over 270,000 miles Steve. He goes to Death Valley and Teakettle junction and Nevada and Arizona.

I know you’re a very knowledgeable mechanic and purist, but… Just sayin’.
 

Retiredwarhorses

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HummerH1 has run without coolers for over 270,000 miles Steve. He goes to Death Valley and Teakettle junction and Nevada and Arizona.

I know you’re a very knowledgeable mechanic and purist, but… Just sayin’.
It’s literally got nothing to do with being a purest…
I’m the one who told you to bypass the cooler…SMH
 

juanprado

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I’d be reaching for JB Weld. Clean it super good first. You could braze it too but that’s a pain.
This and if it does not work, leave the stock unit to do the engine oil only but throw a civy transmission cooler ontop of the stack and adapt the hoses assuming the engine side has no issues or cross contamination.
 
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Green Line Lawn

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This and if it does not work, leave the stock unit to do the engine oil only but throw a civy transmission cooler ontop of the stack and adapt the hoses assuming the engine side has no issues or cross contamination.
thank you, doesnt look like the engine oil side has any issues, may do just that (just run an external cooler for trans), or may pull the stock dual cooler completely and run 2 separate units, just trying to figure out which ones..
*also found an oem cooler on ebay, with a dent, trying to reason with the seller..
 
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