automatic transmission coolers

[idriveadelsol]

Basically, I have a leak coming fro the transmission cooler. Weather it is the fittings or the hose, I have no idea. But I ran a couple of figures and it will cost me more to fix it than purchasing an AFTERMARKET transmission cooler. $30.00

However, I am not familiar with how exactly the transmission cooler works. On the OEM part, the transmission cooler is attached to the bottom of the radiator. Somewhat like this:

but the aftermarket piece is its own entity.

Here is my question: Why is it attached to the radiator? Does COOLANT flow through the radiator cool the transmission? If I purchase an aftermarket piece like:

will it suffice or be better than the OEM transmission cooler?

 

[The motor guy]

So it gets cooled by the cooling fan. They have to put it where airflow will reach it. Mine looks like that on my truck just a little bigger. The transmission fluid flows through that cooler and it is cooled by the airflow.

 

[rshaw125]

Is it the cooler or just a connection/fitting or a hose? I have had to replace hoses before.

 

[daves66nova]

Originally Posted By: motor_oil_madman
So it gets cooled by the cooling fan. They have to put it where airflow will reach it. The transmission fluid flows through that cooler and it is cooled by the airflow.
no, the atf is cooled by the coolant,not the airflow.The atf cooler runs along the inside of the side or along the bottom of the radiator.

 

[deeter16317]

Originally Posted By: daves66nova
Originally Posted By: motor_oil_madman
So it gets cooled by the cooling fan. They have to put it where airflow will reach it. The transmission fluid flows through that cooler and it is cooled by the airflow.
no, the atf is cooled by the coolant,not the airflow.The atf cooler runs along the inside of the side or along the bottom of the radiator.



Actually, it can be either...some radiators are coolant-atf coolers and some are air-atf coolers....it depends on the manufacturer. I've seen both.

 

[SteveSRT8]

yep, my Chrysler ATF cooler is 'segregated' from the coolant even though it is part of the radiator.

 

[NYSteve]

I would very carefully find out where the leak is. There are several cases out there where the radiator failed and mixed coolant and atf, taking out the transmission with it. Would hate to see your $30 workaround resulting is a dead transmission.

 

[daves66nova]

Originally Posted By: NYSteve
I would very carefully find out where the leak is. There are several cases out there where the radiator failed and mixed coolant and atf, taking out the transmission with it. Would hate to see your $30 workaround resulting is a dead transmission.
That dID happen to me once.1,100 later i never used the radiator cooler anymore and just added an auxiliary one.never had problems since.

 

[The motor guy]

This one looked like it was the type that was separate from the radiator making it cooled by air. That type is better. I've never understood how a cooler cooled by coolant is supposed to cool a transmission because a transmission should ideally run around 180-200 degrees. So how do they cool the fluid by running coolant that is the same temp as transmission.

 

[Torrid]

Originally Posted By: daves66nova
Originally Posted By: NYSteve
I would very carefully find out where the leak is. There are several cases out there where the radiator failed and mixed coolant and atf, taking out the transmission with it. Would hate to see your $30 workaround resulting is a dead transmission.
That dID happen to me once.1,100 later i never used the radiator cooler anymore and just added an auxiliary one.never had problems since.


This is why I keep thinking of getting a separate cooler. I just changed the fluid out at 51k miles on my GTO and the fluid was dark red with no burned smell so I figured the factory cooler is more than adequate, but I have been concerned if something went wrong with the cooler and I got Dexcool in the transmission.

 

[Trav]

Quote:
I've never understood how a cooler cooled by coolant is supposed to cool a transmission because a transmission should ideally run around 180-200 degrees. So how do they cool the fluid by running coolant that is the same temp as transmission.


The transmission cooler is usually on the lowest point on the radiator or vertical like in side mounted applications with the return line being the lower line.
The temp is much lower after the coolant has gone through the radiator before it goes back into the engine.

This design is actually a very good design that helps warm the fluid also in cold conditions, some transmissions don't need an additional cooler e.g. 4T65E has a relatively small fluid capacity and a large enough cooling system for the engine size, transmission temps are usually very stable in all but extreme conditions.
Some units can over power the radiator mounted cooler and can benefit greatly from an aftermarket unit.
Oil to air coolers are good but have one inherent problem, they tend to over cool in colder climates during the cold months, running cold is almost as bad as to hot.

One solution is to run the oil to air cooler in series with the radiator cooler which in this case is also helps bring the unit up to operating temp.
Another solution is to run a in line thermostat or use a design which allows the fluid to bypass the cooler when cold like the True-Cool LPD.

http://www.transmissioncoolers.us/

 

[idriveadelsol]

Originally Posted By: NYSteve
I would very carefully find out where the leak is. There are several cases out there where the radiator failed and mixed coolant and atf, taking out the transmission with it. Would hate to see your $30 workaround resulting is a dead transmission.


the leak is either from the fittings or the line... i lost almost a quart until i tightened it a bit. think you misunderstood my post. it basically will cost me more than 30$ to fix... i can DYi... but, all my tools are home and i am back in school. so i guess, I cannot DYi... ha~!

if the OEM system is cooled by coolant, i have to get it fix. i believe honda engineers know a bit more than i do. if it is air cooled, i can swap it out with an air cooled transmission cooler than is 20$-ish.