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Recently installed the Hayden 678 tranny cooler on the front of the condenser using steel brackets.


I had a B & M cooler before and the manual say that position is not the recommended position with the fitting pointing down. It creates air pockets resulting in reduced cooling effeciency.
 

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The factory installed transmission cooler in my 2001 Ford Explorer (V8 with towing package) has the hoses pointing down. This picture is taken from under the car.

149655


I don't say is right or wrong... it's just is. Maybe they would need some kind bleeders?
 

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On a properly installed cooler, yes.
On a tube and fin cooler, yes.

on a plate and fin, or stacked plate cooler, maybe not.

On a cooler that is installed upside down, you will most likely have an air pocket. It may not be huge, but it will likely be there. The bigger the cooler, the higher the chance of an air pocket. It is good practice to install liquid handling devices in a way to make them self bleeding. It is foolish to instruct someone to do it wrong, even if it might work, and defending that is just as bad.

I don't care how a factory installed a cooler, it can still be wrong. Just because it doesn't cause problems doesn't mean it's right or doing it's job completely. I was a hydraulic technician and I have seen all sorts of hokey stuff that "worked" as I guess you could call it.
 

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Like they say, at every first run in the morning of that cooler installation, will have the cold, fairly viscous, transmission fluid pouring trough that radiator, at high pressure.
My gut feel is that there will be no pockets of air left after the first couple days.
If you shake a cold bottle of transmission fluid you'll see how air bubbles kind of are trapped inside the fluid and stay like that for a few minutes. That's how the air gets out from a cooler.

One can check that touching the cooler after a short run, to see if there are places where it's colder, compared to the rest. An infrared camera or laser-guided thermometer would tell for sure if it makes a difference.

On the other hand, this is the factory 4Runner cooler:



It's a baby! Love the 90 degree terminals!!!
 

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The actual location is important too.


Transmission coolers are more efficient when they receive maximum air flow. At Position 1, the transmission cooler is 100% efficient. Position 2, between the air conditioning condenser and radiator, is 75% efficient while Position 3, between the radiator and fan, is only 60% efficient. If positions 2 or 3 are used, a larger transmission cooler will be needed to compensate for the loss of cooling power. If this is the case, choose a transmission cooler that is one or two sizes larger.
 

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Are you sure? I think the up position is not recommended. Sides and bottom are ideal.
I am sure. You can argue with B & M. Here is your proof.
 

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Like they say, at every first run in the morning of that cooler installation, will have the cold, fairly viscous, transmission fluid pouring trough that radiator, at high pressure.
My gut feel is that there will be no pockets of air left after the first couple days.
If you shake a cold bottle of transmission fluid you'll see how air bubbles kind of are trapped inside the fluid and stay like that for a few minutes. That's how the air gets out from a cooler.

One can check that touching the cooler after a short run, to see if there are places where it's colder, compared to the rest. An infrared camera or laser-guided thermometer would tell for sure if it makes a difference.

On the other hand, this is the factory 4Runner cooler:



It's a baby! Love the 90 degree terminals!!!
This position is ok because the fluid come from the top and flowing to the bottom and out. If you had the fitting on the bottom it needs to flow up and then come down to go out. Like Ike said installing it upside down may work but it is going to create air pockets.
 
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