I want to install my trans cooler and it's quite large, half the size of the engine coolant radiator actually. I'm thinking of running it in series after the radiator. So trans - radiator - trans cooler. Good or not?

Any recomendations?

 

cooler after radiator yes. If you put it before, the hot engine coolant will just reverse what ever the cooler did. On transmission, top line is return. Good luck finding a place to put it.

 

After the radiator for sure.

 

I personally just bypassed the radiator all together, and connected my lines straight to the external cooler.. Less fittings = less possible restriction, however small, and less possible leaks. Simple=better IMHO.

 

I bypassed to radiator too.

 

What about trans cooler - radiator - trans?

The trans fluid holds much more heat than what resides in the coolant so wouldn't it make sense to cool the trans first and then assuming the trans fluid temp is still higher than the coolant, then route it through the radiator?

Water has a much larger heat carrying ability than air so I'm going to try it like that. Don't want to rob the engine of power either

 

I bypassed the radiator also

 

I tried bypassing the radiator completely with a B&M 36k cooler and the temps went up almost 20* over what it was running in series after the factory cooler. The heat transfer is much more effective inside the radiator, so it cools it the trans fluid down to the coolant temp, then running it through the aftermarket cooler knocks another 10-15* off of it. Unless you're gonna put a pusher fan on the aftermarket cooler, I would avoid bypassing the factory cooler and instead run them both in series, with the aftermarket cooler after the factory cooler.

 

Running the trans cooler pre radiator seems to be working really well. The radiator doesn't get hot at all even after a good thrashing which makes me wonder how much heat does the stock in tank trans cooler set up dissapate back to the engine?

Cool engine and cool trans are equally important IMO.

My recommendation is trans - trans cooler - radiator in tank cooler - trans. I haven't hooked up a temp guage to the trans as yet but the fact that the last link in the cooling loop is vastly cooler seems like confirmation of that theory

 

Let's analyze this for a second:

Trans Out = ~180
Trans Cooler (ambient) = ~85
Trans Cooler (Radiator) = ~210
Trans In = ?

So you take the fluid that is at say 180 degrees coming out of the trans, route it to a heat exchanger exposed to ambient temps of ~85 degrees. This is cooled off tremendously, then you introduce it to a heat exchange that has the fluid temp of ~210 as the cooling medium. You just warmed up the trans fluid and negated the trans cooler you installed. You want the trans fluid to go to the radiator cooler first, then to the cooler exposed to ambient air to further cool it down.

This is how my setup is, and track testing on a road course (much more abusive then drag racing or street driving), my temps stayed under 210 during a 30 minute session.

EDIT: Looking over your layout again, are you asking about placement of the cooler relative to airflow? If so you want the trans cooler in front of the A/C condensor, while having the radiator behind the A/C condensor.

 

I take your point but I think yours and my angles are different. Either way (radiator 1st or ambient trans cooler 1st) the trans fluid will be vastly cooler than if it was only routed through the radiator trans cooler alone. Keeping this in mind then, my primary concern is to not elevate the radiator temp more than need be as engine longevity and performance consistency are directly related to engine operating temps.

So I guess since the trans temp is improved much more than if it didn't have an external cooler at all, I just want to look after my engine too. The whole aim of my set up is to provide a slightly under optimised trans cooled temp (your concern I guess) but at the same time find a compromise between the 2 on board cooling systems (trans fluid and engine coolant) to maintain a more stable overall operating temperature.

I agree with your figures somewhat and haven't had a chance to guage all the temps as yet but the coolant temp guage is a full 1/5 lower on the dash consistantly and the engine is more stable temp wise. That being said, the way I have set up the braided lines allows me to re route them to change the sequence if the need arises.

This is the set up, the braid goes all the way to the box

 

you have it all wrong and here is why!!!

Like 12secss said
Your set up is taking trans fluid that is roughly 220* coming out of the trans,running it through the ext trans cooler and droping it to 190 or so then running it through the radiator cooler only to raise the trans fluid tep up to roughly 210* in which you effectively done squat at reducing the trans fluid tep.
As far as the trans fluid warming up the radiator fluid and making the motor run hotter and in turn loose power, not going to happen. Why you might ask well for one thing even if the radiator fluid was 20* cooler you might gain 5hp if that. It won't matter if you dump extra heat into the radiator fluid as the system is designed to handle that heat and disipate it to the air and your motor will still see a coolant tep of 210* reguardless as the fan tep settings as well as the thermostat work together at keeping a constant 210*. Here is a simple example for you to understand what im saying. If the outside air is 30* what is your motor tep when its warmed up--um 210*. Now what is the motor temp in the summer if the outside air is 90* yea you guessed it 210*. How could the radiator fluid still be 210* in the summer when your putting 60* hotter air through the radiator. It simply disipates it more due to the run time of the fans to keep the temp @210. So you see it won't matter if you have the trans fluid thats hotter,run through the radiator as the fans will still keep the radiator fluid @ 210. If you really want to cool the motor down you going to have to A. Replace the stock t-stat to a lower opening temp and B. you have to reprogram the fan turn on/turn off temps to have any effect on the radiator fluid temp. In your case you could just reprogram the fan turn on/off temps a little bit to take a few extra * out of the radiator fluid but it wont be much due to the fact that the stock t-stat will close shut in an attemp to keep the radiator fluid to 210*

 

Bypass the radiator, that way the factory did it is a joke, just like running the PS cooler through it on some cars.

Get 2 approx. 10"x10" coolers, run them in series, and put them up in front of the condensor on both sides, connected the frame that runs across the bottom that the air dam is attached to. They don't effect coolant temps AT ALL.

The tranny will love you. 180* off the tranny going through two coolers places in that location will drop your temps about 40* before going back to the tranny. That kicks ***. Then put a power steering cooler under that frame rail and cut a strip out of the air dam so air can hit it.

Takes about 1 1/2 hours to do all 3.

 

​​​​​​ Depending on make and model of your vehicle.. I'm sure, like mine, they make aftermarket thermostats that will open at lower temperatures.. but I also think running the cooler after the radiator cooler is a wiser decision..due to the fact that they also make aftermarket radiators that come all aluminum..and thicker... And do to engine bay space, sell thinner electric fans.. a lot of little money, can all add up to big savings when it comes to both the engine and transmission...

 

I was getting high temps with the B&M so I switched to a hayden 679 and my temps stay nice and cool with the rad bypassed. Even fits with the SSRA. I have a performabuilt 4L60E stage 2 with 4000 stall and even beating on it in 90 deg weather the trans never goes above 165. Normal cruising on 90 degree weather and it stays 125 and lower. Trans temp sending unit is in the pressure test port on the driver side of the trans and I have a truck transmission pan.

https://ls1tech.com/forums/automatic...er-ssra-3.html

 

I find that the temperature reading is more accurate in the pan.