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More questions about Aux Trans Cooler for towing

mhbell

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I have read many different opinions in this forum about a installing a Auxillery transmission cooler. I need to get some clarification on the subject. I have a 2009 Avy LT / LT1. It has no aux TOC. I installed a Prius Brake controller. I plan to tow my 23 ft travel trailer which weighs 4500 Lbs loaded. (Iweighed it on a Cat Scale). I live in Utah which has hot and cold weather extremes. I plan on 2500 mile round trips a couple of times a year to Texas. We have lots of mountains to travel for camping and fishing. I have been told I should get a AUX TOC. Now There are several coolers on the market, IE Tube & Fin, Stacked Plate, Plate & Fin and Heat Sink. Those with Cooler Bypass and those without. The ones with cooler bypass are more expensive. Do I really need one with bypass even if installing after the radiator in the return line? What about installing in the bottom line? Since we have temp extremes winter and summer I have having a hard tim as to which cooler to get. One with bypass or one without. One that is Tube and Fin or one that is Stacked Plate. I really don't want to have to spend a lot of money if a less expensive cooler will do the job. What are your thoughts. Ive been looking at Hayden and Compressor Works TOC's. Appreciate your comments.
Mel
 

ygmn

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Yes if I was you and planned on keeping truck along time...
adding a cooler as causes more GOOD then BAD from not having one.

As to which one...
well coolers should be sized by BTU but they do not... so hard to say which one is right fit.
The bypass valve is interesting as it allows tranny to get up to temp and stay there on cold days and when not towing and heck when cooling is not needed.... which is a good thing as long as it works!
 

mhbell

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I have pretty much decided to get a 20,000 BTU TOC. this is the size recommended for pulling a 4500 Lb 23 foot trailer. Still undecided wether to get one with bypass or not. If I don't get one with bypass I will probably go with Fin and tube. I worry that if I go with one installed in the return line, that doesn't have the bypass then the trans fluid would be to cold in the winter time which could be as bad as to much heat. On the other hand if installed in the input line (bottom of the radiator) then it would not need the bypass but would not be as efective at cooling the trans fluid. The temp would be the same as the radiator temp or almost the same.
Mel
 

mhbell

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Well I bit the bullet and decided to get a B&M 70264 Super Cooler With Stacked Plates, 19000 GVWR, 14500 BTU and a Fluid Bypass. I will install it inline with the factory radiator coolers return line. My GVCWR is only 11000 Lbs with the trailer. I should be in good shape with this trans cooler.
Here is some info on the cooler.
It is built out of lightweight aluminum alloy and features a revolutionary 'stacked plate' design with multiple oil flow paths. The unit monitors resistance to flow by allowing a controlled amount of ATF to pass through a self-regulating orifice. Controlled by viscosity, thicker ATF is returned directly to lube through two bypass openings in the stacked plate core, while thinner ATF is directed through the core to cool as operating temperatures increase.
I will try to detail the install with Pictures after the cooler arrives on Wednesday.
Mel
 

Randy

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Get the B&M 70266, you can't go to big and you don't need a bypass. The factory radiator cooler will not let it get to over cool, anything above 160 deg and below 200 deg will help get the most life out of your trans. This is the one I have and driven in 20 deg temps with no issues, temps stay within range...
 
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Loggie

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I did one back on my 02.


got awesome results. I've also ordered one ( Four Seasons 53000 Ultra-Cool Transmission Oil Cooler ) for my '12 but have not installed it yet. looks like there is already one there so I might add it along side. can't hurt:unsure:
 

mhbell

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The one I ordered comes with everything I need.
The SuperCooler 70266 comes with 1/2″ NPT fittings which will require extra fittings, but allows for -6an or -8an transmission lines. Like all B&M aft coolers, the 70266 also has a low pressure drop system to prevent over cooling.
The cooler bypass is installed in the cooler already guess they call it the low pressure drop system. Its true that you can't go to big, but This is all I will need pulling a 4500 Lb travel trailer on a trip maybe twice a year.
Mel
 

Loggie

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...agreed and make sure you post the install ;)
 

Randy

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Nice job, your trans with appreciate it ...
 

CenFL Avalanche

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I installed a Hayden one back in 2017 or 2018 and it has helped a lot towing my travel trailers. I stay under 190 degrees most of the time in hot Florida summer heat. I have also found that tow/haul mode also keeps the temps down. I just used some square aluminum to brace it to the A support brace on the truck.
 

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Loggie

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