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Transmission Hot on display, not towing anything

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  #11  
Old 07-29-2024, 05:03 PM
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Originally Posted by H2x2
I installed the true cool large external cooler bypassed the built in to radiator one, it's barely moved temp Guage even on hottest days, I'd recommend it to everyone, there's a few threads on installing this one, old threads

How is a transmission cooled?

In almost all vehicles with an automatic transmission there is a transmission cooler placed inside the radiator. Most standard transmissions do not make as much heat and therefore do not have a cooler. The cooler for the automatic transmissions are placed inside the radiator, the reason behind this is the antifreeze provides the perfect environment. It warms the transmission fluid up when it’s cold and keeps it from getting too hot in extreme heat.
An auxiliary cooler is a completely separate transmission cooler that is typically mounted somewhere in the front of the AC condenser. While these coolers are helpful they are not quite as effective as the coolers that are mounted inside the radiator. The reason? The auxiliary cooler is cooled by air flow while the cooler inside the radiator is surrounded by antifreeze which is a controlled environment.

For this reason we recommend never eliminating the cooler inside the radiator. If you want to increase cooling capacity we recommend adding an auxiliary cooler. This way the transmission is being cooled by two different coolers; one with antifreeze and one through air flow.
 
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  #12  
Old 07-29-2024, 08:04 PM
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Originally Posted by MixManSC
If its indeed overheating then an external cooler could help. As legerwn said though, a fan will do nothing at all unless its overheating when going under about 30mph. Above that speed even factory electric fans shut off since they are pointless when the air moving at speed is far greater than what a fan can provide.

I suspect a failing sensor or possibly a clog somewhere though.
Let me throw this out for Comment..... Is it possible that the water pump at high rpm is not doing it's thing? Or is the serp belt slipping at higher RPM? Yes/No?
 
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  #13  
Old 07-29-2024, 09:46 PM
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On the topic of never bypassing the radiator cooler, was told they failed on h2 often, that's why I started looking into it originally, the results were always running cool
 
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  #14  
Old 07-30-2024, 10:45 AM
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Originally Posted by 2004H2
I bought a 7” electric cooling fan, 800 CFM, going to try it out and see what happens, there’s hardly any space between the hood frame and the trans cooler, this looks like it will fit snugly, last year had a new Aluminum radiator put in, wouldn’t think that would be an issue, Amco said it would be hard to figure out why the overheating on highway because it doesn’t do it in city driving,they put there tester on it everything normal, no codes, also suggested replace cooler with a Brand new unpainted one, the black paint cooler holds in the heat, where the aluminum cooler dispels it….I’ll keep you updated on the progress…

thanks for input….Rick
installed 7 inch fan,tight fit when closing hood, squealed then stopped, 1st thing noticed was my a/c was ice cold, in about 2 minutes, in 94 degree air, usually takes 6-10 minutes to get cool air out of vents, the stock cooler is so thin, I thought it was deep and it’s not, haven’t taken on long drive yet, but I would think an external cooler is the ticket if this doesn’t pan out, going on turnpike Saturday,will see what goes

Rick
 
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  #15  
Old 08-06-2024, 08:06 AM
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Default Your right, fan didn’t help trans….
Originally Posted by legerwn
a fan will not help, there are no fans that can move the amount of air that is going across the cooler at 70 mph, if it were getting hot at low speeds in town then a fan might help.
I personally don't think an aux fan does much if any good as the radiator fan is pulling air across the cooler already.
Its usually a requirement that the cooler and lines get flushed and tested when the trans is rebuilt as part of the warranty, I wonder if they did.
I've read that some trans allow some of the fluid to bypass the cooler while in OD, next time the temps on the trans start coming up take it out of OD and see if it cools down.
I'm with Gavin on this one you may have an issue with the trans or the temp sensor in the trans,

Neal
put fan on and a made big change in the a/c performance, when truck is hot inside, transmission wise made no difference in town, went on the pike for 1/2 hour at 80 mph and didn’t run hot, came up a little, so I’m putting on an additional cooler today at AAMCO, there installing it today….

Rick
 
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  #16  
Old 08-10-2024, 09:26 PM
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Default After market cooler for Transmission
Originally Posted by legerwn
a fan will not help, there are no fans that can move the amount of air that is going across the cooler at 70 mph, if it were getting hot at low speeds in town then a fan might help.
I personally don't think an aux fan does much if any good as the radiator fan is pulling air across the cooler already.
Its usually a requirement that the cooler and lines get flushed and tested when the trans is rebuilt as part of the warranty, I wonder if they did.
I've read that some trans allow some of the fluid to bypass the cooler while in OD, next time the temps on the trans start coming up take it out of OD and see if it cools down.
I'm with Gavin on this one you may have an issue with the trans or the temp sensor in the trans,

Neal
updated cooler installation by AAmco, the cooler they installed is 4 times the size of the stock one, will show it works out on my next turnpike run in 3 weeks

Oem replacement that is going back to Amazon

Installed by AAMCO
 
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  #17  
Old 08-11-2024, 08:30 AM
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that should keep it cool, looks good

Neal
 
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  #18  
Old 08-11-2024, 11:01 AM
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How Much was that Bad Boy $$$$ and who is the Mfg...?? Loks nice.
 
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  #19  
Old 08-12-2024, 12:50 PM
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Originally Posted by Mark R
How Much was that Bad Boy $$$$ and who is the Mfg...?? Loks nice.
the total bill says $550 install, the cooler says $109.00 installed and warranty by AAMCO, the cooler manufacturer unknown, the mechanic said they have 35 different sizes coolers in stock at all times…..
 
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  #20  
Old 08-12-2024, 03:43 PM
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Originally Posted by 2004H2
the total bill says $550 install, the cooler says $109.00 installed and warranty by AAMCO, the cooler manufacturer unknown, the mechanic said they have 35 different sizes coolers in stock at all times…..
Well now you have to see if it does the Job...Hope it works out . That price isn't bad in todays market.
 
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