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Aftermarket trans cooler

AZjeepin1

NAXJA Forum User
Location
Glendale, AZ
Is it kosher to run tranny fluid only to an aftermarket cooler as opposed to running it through the radiator + factory cooler?

Also, can an aftermarket cooler be mounted flat or does it HAVE to be mounted vertically? I'd like to get it out of the way of the radiator up front.
 
You don't have to keep the factory radiator cooler. Some people think it's a good idea to keep a little heat in the oil, as an automatic trans needs to be up around 160deg or so for best operation. In the desert, running "too cool" should never be a problem for you. ditching it should cause no problems.

The cooler can be mounted in any orientation you like and have room for. The only requirement is that it gets air flow through it. Most people mount the cooler in front of the radiator for airflow. if you mount it somewhere where air can't flow through it/out of a moving air stream, it won't do any good. If you're mounting a cooler with a dedicated fan, it can be mounted anywhere.
 
You don't have to keep the factory radiator cooler. Some people think it's a good idea to keep a little heat in the oil, as an automatic trans needs to be up around 160deg or so for best operation. In the desert, running "too cool" should never be a problem for you. ditching it should cause no problems.

The cooler can be mounted in any orientation you like and have room for. The only requirement is that it gets air flow through it. Most people mount the cooler in front of the radiator for airflow. if you mount it somewhere where air can't flow through it/out of a moving air stream, it won't do any good. If you're mounting a cooler with a dedicated fan, it can be mounted anywhere.

How about the intake or exit side of the cooler if it's mounted vertically? Should the hot side of the trans go to the bottom inlet or should it go to the top?? The reason I ask is cause if it enters in the top of the cooler then the fluid will drain down and be ready for reentry to the pan (suction/return side) if it enters at the bottom of the cooler there could be air when the trans starts sucking in fluid from the return side which may have drained down. But if the pan has fluid I don't see how it would matter, did I just answer my own question??? Does this make sense to you??
 
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Yes, for optimum flow characteristics, they must be plumbed a certain way... quoted from grimms an fitting thread...
it took me a while to dig this info up, so I'm adding it to the thread for future reference.


the forward connection on the transmission is the output, and should run to the lowest point on your cooler, and the rear most port is the return line. the reason for running it this way is so the transmission is pushing the fluid against gravity to move it through the cooler, instead of reaching the highest point and starting a siphon effect and draining back to the trans before it's cooled properly. It will likely only make a small difference in cooling, but this way will make the cooler perform the most efficiently.

:cheers:
http://www.naxja.org/forum/showthread.php?t=1045807
 
The last XJ I put a trans cooler on, I mounted it below the radiator in that winch port on the lower radiator support. Worked fine and was out of the way of the radiator.
 
I run a 25,000 lb cooler independently of the radiator.

cooler01.JPG
 
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