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What is the correct way to install a trans cooler

Digger87xj said:
Air in a cooler is NEVER going to cavitate the pump, cause cooling issues or cause aeration after the first time the torque converter locks up. It simply won't happen.
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care to back that claim up? pretty much every transmission expert and cooling expert has disagreed with you. including the MFG of every cooler I've ever seen.
 
rockclimber said:
care to back that claim up? pretty much every transmission expert and cooling expert has disagreed with you.
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Likewise, can you prove that is does? Unless the cooler is clear there is no way to really know.

I will concede, a plate style could trap some air. big deal.

A serpentine tube cannot.

Every install guideline for plate style I see say it MAY trap air and MAY cause cooling inefficiencies. It won't aerate the fluid, and won't and I dare say CAN'T cavitate the pump.

AFA I can tell their statements are a CYA statement.
 
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Everyone who says it's an issue probably doesn't realize that the torque converter drains about halfway when you shut the jeep off. Or just how much pressure there is in the cooler lines, it makes a hell of a mess when one pops off or gets punctured by a passenger side UCA let me tell you. Mine shot fluid about 4 feet to the side out of a tiny pinhole around 20-30 thousandths of an inch in diameter, that takes some serious pressure.

No way that air is going to stay in there in any meaningful way when you fire it up, and no way that it matters.
 
kastein said:
Everyone who says it's an issue probably doesn't realize that the torque converter drains about halfway when you shut the jeep off. Or just how much pressure there is in the cooler lines, it makes a hell of a mess when one pops off or gets punctured by a passenger side UCA let me tell you. Mine shot fluid about 4 feet to the side out of a tiny pinhole around 20-30 thousandths of an inch in diameter, that takes some serious pressure.

No way that air is going to stay in there in any meaningful way when you fire it up, and no way that it matters.
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yup..
Had a quick disco pop on me just this morning. NOT pretty.
 
kastein said:
Everyone who says it's an issue probably doesn't realize that the torque converter drains about halfway when you shut the jeep off. Or just how much pressure there is in the cooler lines, it makes a hell of a mess when one pops off or gets punctured by a passenger side UCA let me tell you. Mine shot fluid about 4 feet to the side out of a tiny pinhole around 20-30 thousandths of an inch in diameter, that takes some serious pressure.

No way that air is going to stay in there in any meaningful way when you fire it up, and no way that it matters.
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that doesn't mean shit if there is air in the cooler or not.

just because you *think* there is enough pressure to purge the system does not make it true.

and yes, a tube style can trap air. not as much, nor as easily, but it can.

whether or not the fluid will aerate and the pump will cavitate is a matter of luck. but why risk it.
 
rockclimber said:
that doesn't mean shit if there is air in the cooler or not.

just because you *think* there is enough pressure to purge the system does not make it true.

and yes, a tube style can trap air. not as much, nor as easily, but it can.

whether or not the fluid will aerate and the pump will cavitate is a matter of luck. but why risk it.
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This tells me how much you know about fluid dynamics.
 
Carroll Smith, Indy and Can Am car builder to only name a few, says that stacked coolers should be installed either ports up or on the side with the inlet on the bottom. Makes the fluid flow through more rows that way. I only know this because I have a big Earls cooler I'm installing next week and have been studying it.
 
I could have sworn it was more like 80-90psi, but 20-30psi is a lot more than I've heard from most people who believe that putting a trans cooler sideways instead of vertical is going to make a difference.
 
The "line pressure" spec in a transmission manual, which is high, is not what the cooler sees.

As for correct mounting, I can see how air can get trapped, especially in a stacked plate design. Several cooler manufactures recommend in mounting the ports to the side or top. I personally prefer to be on the safe side and have them to the side or up.

Also, this was a concern when I did my cooler. http://naxja.org/forum/showthread.php?t=1011262

RCP Phx said:
Not when there are parallel paths to flow from.We had 2 plate coolers mounted fittings down,Infared showed no fluid at the top of the coils!They now flow once turned sideways and also make the input on the bottom and return on top.
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lol

I have seen 240psi on GM trans ... just went searching for mopars and the AW4.... thought I would edit first just in case... thinking 75-120 but I cant remember for sure

EDIT
all my information shows "converter pressure" but doesn't give a value as to what that would be but IIRC from my dealer training class it runs 75 to 120 psi

Also, the AW4 has an internal cooler bypass valve. if the trans is not up to temp there is very little flow to the cooler. So, those with fears of thick oil shifting problems in the winter need not worry about by-passing the radiator cooler.
 
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I'd guestimate between 15 and 30 PSI running through the cooler. With the lower number being more likely than the higher number. No real reason to have higher pressure, the fluid isn't doing any work, it is just circulating.

I had it all apart a few days ago, if this thread would have popped up then I would have cut a "T" in there and done a pressure test, just out of curiosity.
 
Digger87xj said:
Also, the AW4 has an internal cooler bypass valve. if the trans is not up to temp there is very little flow to the cooler. So, those with fears of thick oil shifting problems in the winter need not worry about by-passing the radiator cooler.
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Are you sure? When I was flushing the cooler by leaving the line disconnected I got a lot of fluid in very little time, and the transmission was at ambient temperature (high 60s). I didn't actually measure it because I was so startled by where the fluid came out (it wasn't the end I expected!), but I had to put in nearly a quart and the engine was on for only about 10-15 seconds.
 
I have a 2000 xj getting ready to install a dirt bound aux cooler and fan my question is what direction is the fluid flow iv heard different thing does the fluid enter the bottom of the radiator and go up or does it enter at the top and flow down to the bottom line
 
HappyDog said:
Are you sure? When I was flushing the cooler by leaving the line disconnected I got a lot of fluid in very little time, and the transmission was at ambient temperature (high 60s). I didn't actually measure it because I was so startled by where the fluid came out (it wasn't the end I expected!), but I had to put in nearly a quart and the engine was on for only about 10-15 seconds.
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Yep, it's called out in the hydraulic schematics.
 
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