Transmission oil cooler
 

Hi all. I've just had to replace the solenoids in my box but while waiting for the bits to arrive, I've done some digging. I can't remember where, but I read about adding a fan assisted oil cooler to help keep the temps down. Is it worth considering or is it just one of those things that someone did but isn't really required. I don't live in a normally hot climate, mostly warm in summer or cold and wet in the other seasons.

I have tried to search the forums so sorry if I missed a thread just like this.

Thanks.

A transmission cooler is a good idea, no need for an extra fan if you mount it up front the radiator fan pulls plenty of air through it. I put a Hayden 405 on mine.
https://cimg7.ibsrv.net/gimg/www.che...e95b35ca65.jpg

It does currently have one which I assume is stock but it's not very sizable. I shall have to look into what I can source. Thanks for the very quick reply!

Mine had the stock auxillary cooler also, trans temp would still get up to 220 during normal driving, the stock cooler is not very big and most XJs only had the cooler that's in the radiator.
https://cimg9.ibsrv.net/gimg/www.che...8443d8de1e.jpg


https://cimg2.ibsrv.net/gimg/www.che...5810c29265.jpg

You live in the UK, which I'm guessing oot444e didn't realize before posting his responses. .
We survive with the factory one like yours here in Arizona.

Waste of time and money.

And actually, the part in the radiator is a heat exchanger, not only a "cooler".
It helps bring the trans temp up.

I guess if you just drive around on the street with factory size tires and don't much offroading you will be fine. When you are working them the transmission will get hot pretty easily, I have seen them overheat and puke fluid out of the dipstick tube or blow out the front seal. A bigger cooler certainly helps keep it cool, under those conditions, also I still used my heat exchanger in the radiator I plumed the cooler in after that.

Road use - Yep
Factory tyres - Yep
Off roading - Limited to a small dirt track

I guess factory will suffice. Thanks again.

Do you off road alot in the summer? if not the (OEM) factory cooler on the front is plenty good, no aftermarket fan needed.
The OEM cooler is fine for towing also,,if you do alot of caravaning.

I have two coolers on my 2000. The factory and Aftermarket, they are in series looped together.
I took the aftermarket one out of the loop last winter do the trans not getting up to temp.
Now if you do alot off road and crawling around in the summer while its hot, hot out.. I would look into a bigger cooler.
Or move the factory cooler over to where the electric fan is. Then toggle switch the electric fan to turn on when you want to pull air over the cooler..
there are threads here in Cherokee Forum on how to toggle the e-fan to turn on when you want it too.


Like mentioned The one in the radiator is a heat exchanger,,Why is it called a Heat-Exchanger?,, its job is too cool,,and to heat the oil.
it will heat up the fluid to operating temp and maintain that temp by pulling in heat from the hot water in the radiator.. This is needed in cold snow climates that see temps in single digits or negative temps.
Now if in a hot climate the one in the radiator will cool the fluid and help it not get too hot.. Its not really a cooler so it will kinda keep the temps ok.. start to over heat the radiator water/motor and watch the trans temp go up.
A coolers job is to cool,,thats it. You dont want a cooler allowing stuff to heat up. Whats the point of calling it a cooler then?


Here is a pic a factory cooler. This is located in front of radiator


https://cimg8.ibsrv.net/gimg/www.che...8b892b70d8.jpg


This is a pic of the heat exchanger inside the radiator..


https://cimg6.ibsrv.net/gimg/www.che...f3915b1bf8.jpg

If you just have the radiator one and not factory cooler and do off road in climates that are hot.. I would look into a aftermarket cooler.

If just driving around and little off road driving/towing,, Then the OEM factory cooler is fine.
Cooler not exchanger..lol

You will be fine..

Do they all have the heat exchanger in the radiator or is it for certain markets? I had to do my AC condenser so have had the front end off but can't say I noticed anything looking like that.

Im pretty sure they all do.. I have not seen one without..at least not on my end of the world.
Its on the inside of the radiator.. You wont see it unless you cut it open.


the H-Exchanger is located where red arrow is pointing..

The green arrow shows where the transmission lines hook up to the exchanger that is located on the inside.


https://cimg9.ibsrv.net/gimg/www.che...99fd5133a7.jpg

Well I didn't tear it down that much so that explains why I haven't spotted it. Good info to know though. Thanks.

Technically any cooler is a heat exchanger.

Here's my setup. Cooler is from B&M and is routed after the factory heat exchanger.

https://cimg0.ibsrv.net/gimg/www.che...dbac265595.jpg

I like those stacked plate coolers, lot more surface area for a given size. I've got one on the way for my latest XJ along with a trans temp gauge. In the past I've used regular tube and fin coolers and that's worked good as well.