Whats your take on trans coolers? Run them before the radiator or after the radiator? Some people say run them after so they will cool off what the radiator did not, some people say it does not make a difference. I how ever have the theory that they should be ran before they enter the radiator and here is why.

#1 If you run it after it comes out of the radiator and the weather is cold the fluid could be cooled too much and never reach operating temperature to evaporate any moisture in the fluid, plus your temps would go up and down depending on how fast you was driving, outside air temp, idling, ect ect.

#2 If you run it before it goes into the radiator it would help take the strain off your entire cooling system because now your radiator is not trying to cool your motor and a super hot transmission. Plus your tranny fluid should always be at the same temp leaving the radiator depending on what thermostat your motor is using. If you was diving in real cold weather and the cooler actually cooled it below operating temp the radiator would actually warm it up.

What does everyone think about this?

 

I have seen several factory setups with the cooler after the radiator. I did mine after and have had no problems.

 

Tranny fluid is cooler then your water temp. And run it after the radiator.

 

some good information here

https://www.thirdgen.org/forums/tran...n-coolers.html

and here

https://www.thirdgen.org/forums/tran...whats-out.html

Im fixing to add an external cooler, so Im very interested in this conversation as well.

Seems like a very good arguement to run the external cooler before the radiator cooler.

 

my tranny cooler is in front of the radiator.... i deleted my ac so i dont have the condenser..... beaten the crap out of my 700r4 and has cherry red fuild...... lowering tranny temps does wonders....

 

He didnt mean infront or behind the radiator. He means the tranny lines going from the radiator to the cooler and back or to the cooler first then radiator and back to the transmission.

 

lmao i did not catch that, but umm isnt hooking up a trans cooler suppose to take it off the rad completely? to help cool the water down better or something?

 

It all depends on how you want to run the cooler and if the cooler you have is big enough to cool the transmission by itself properly. Either way is acceptable.

 

every model trans is different. But if the fluid is too cold, trace amounts of water can collect that's bad.
I have a thing called a "thermal bypass valve" on my Jeep. It keeps the fluid at an almost constant 140*F by routing the fluid through the cooler (which is more than big enough to keep it cooled) when it's above 140*, and bypassing the cooler and running straight back to the trans when it's below 140*. There's no electronics, it worked kind of like the thermostat for the coolant.

before i got the bypass, I plumbed the cooler in before the radiator so it wouldn't get too cold in the winter, i want the radiator to heat it up. My Jeep trans doesn't shift right when the fluid is <80*.

 

Transmission cooler advice will vary depending on if you live in Alaska or Florida. Generally most of us either drive our cars in summer only (northern climates) or all year round (southern climates). As such, we're buying transmission coolers to keep the fluid cool instead of warm.

I don't think running the cooler before the radiator would work because most of the time our radiator is too warm to keep the fluid cool. Hence why we bought transmission coolers in the first place. How about when you're sitting in traffic and the radiator is sitting at 200-220°?

Good transmission coolers will have a bypass built into them (check out the Long TruCool coolers like I'm running). They'll bypass the cooling area during cold temp and then run it through the cooler during hot temps.

My transmission cooler doesn't even run through the radiator. I like it this way because if your radiator boils over, your transmission fluid stays cool. Also keeps the radiator a bit cooler than running the transmission cooler through it as well.

I live in the hot south though. If I lived some place where I had to start my car up when it's 0°F outside, I'd run it through the radiator first. That way the radiator would act as a warm up device for the transmission fluid on cold starts.

 

i took out my ac and my set up goes...

tranny>radiator>tranny cooler>tranny

no problems yet figure since i put a set of 3.73 it wouldnt be a bad idea(kinda like insurance or peace of mind)

regardless how u do it, it will be benificial

 

have had an aux trans cooler in line since first year I had it - 84 Z-28 305HO w/700r4 - it is plumbed into the top trans oil line fitting on radiator - so , silly question, is the trans oil line flow from trans to top radiator fitting then thru radiator and out/back thru the bottom fitting to the trans, or the other way around? just wondering... am I plumbed "before the radiator"or after? thx