tranny coolers

[79cherokeechief]

when installing a tranny cooler do you still use the one in the radiator or will the the one you install in front of the radiator be enough??? ive been eyein one at the boneyard off a wagoneer for some time and thought it couldnt hurt to add it to my cherokee.

[gsmikie]

you still use the one in the radiator

[coolram]

Yes you route thru the one in the radiator then thru the aux cooler.

[tbent78]

The one I purchased new said to run it through the radiator and then the cooler. But they also had on the box if you didnt have the cooler in the radiator you could go direct to the transmission cooler. I ran mine through the radiator cooler and then the tranny cooler, the only problem was it was too late for the tranny and is now getting rebuilt.

[Va-Rob]

The purpose of running in line with the radiator is to warm the fluid in cold conditions.

Rob

[79cherokeechief]

ok thanks for the info.

[Lugnut]

I've read different views on this. One says it's good to run it thru the rad. to warm the fluid. The other, just run it direct thru the aux. cooler, that you can't run an automatic trans TOO cool.
I've talked to two people, one off-roader who is running it direct and his is doing fine; the other who rarely gets offroad and says his is doing fine.
But, if you live in San Antonio, you will prob. never have a problem with getting your trans. warmed up, whether winter or summer. I'd run it direct.

[rockjeep44]

Direct...especially if you wheel hard.
-Andrew

[Serious Johnson]

Now I've briefly wondered about this before, and still don't quite get it (maybe it's this cheap beer). Seems to me that when the lube is hot, then the greater temperature differential between it and the atmosphere would cause the add-on cooler to be more efficient, and also reduce heat loads to the radiator if it went to the add-on first. When it's cold, then the radiator would warm it before it's returned to the trans. Am I missing something?

:-

[blt2krl]

All the coolers I have ever seen saw to go through the AUX. cooler first and the fthrough the radiator. Course thats not saying much.

[Nobby]

You could get all fancy like and put a thermostat in the system to bypass the rad. cooler, to cover both bases.
I found one the other day whilst surfing that operates at 180F for transmission oil.

Edit.
hmm just thinking about this further than one beers worth. Not sure if you'd be able to start bypassing the rad cooler whilst still sending oil to the trans cooler. Would most probably be quite fancy if you pulled it of

Edit. Upon even further reflection running it direct to the cooler (taking the rad cooler out of the loop) assumes that you are not cooling the oil but heating it when it goes to the rad cooler as well. Id be inclined to think like Damage Inc said that it gets cooled in the rad cooler and then further in the trans cooler. Thats enough beer and thinking for one day.

[ November 09, 2002, 12:30 PM: Message edited by: Nobby ]

[Joe J-Truck]

I always thought it's better to not run the trans fluid through the radiator.. but if gsmikie says so... He's a mechanic who knows his nuts & bolts..
Hey Mikie, would that heat up the fluid more than cooling it?
Explain this if you would to us humble jeepers of lesser knowledge.

[Damage, Inc.]

Run through radiator first. Even during heavy off-roading, the radiator's temperature is cooler than the transmission fluid. The atf is going to get cooled down to engine temp (210-ish) before going to the tranny cooler for further cooling.

If you run straight to the tranny cooler, you're losing some cooling.