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Transmission cooler strain on pumping

Hi, I am looking at adding an automatic transmission cooler to my Toyota Corolla 1999 with 110K miles. I am not towing anything, just want to do preventive things to extend the life of the transmission. My concern is whether it will put more strain on the pump that pushes the ATF through the additional pipes/tubes/plates in the cooler. Could it make that pump die sooner - thus reversing the intended effect of the cooler? Thanks ahead!

It will not add any noticeable strain to the pump.

Unless you are towing a trailer, carrying very heavy items most of the time, or racing up Pikes Peak in July, you don’t really need a cooler.

However, it is important to change the fluid and filter every 40,000 miles or so, even if the owner’s manual says to leave it till later. The cooling system should also be flushed every 40,000 miles or so to make sure the transmission fluid cooler inside the radiator works well. An external auxiliary cooler can’t take the place of these preventive activities.

I have installed 5 coolers over the years, but in all cases I towed a trailer. My 2007 Toyota is not going to tow anything, so it won’t get a cooler; just the tender loving care described above!

Thanks! I’ve been doing all the fluid and filter changes like you said. Just want to be more careful because I’ve seen so many friends’ car transmissions went kapuk in their early 100K.


The cooler wont hurt a thing and as far as changing the fluid, every 25-30k miles regardless of what the owners manual says.



ust want to be more careful because I’ve seen so many friends’ car transmissions went kapuk in their early 100K.

If you ask them, I’d bet you would find out that they did not bother changing the transmission fluid nor did they clean the filter.

I usually say a minimum of 40,000 miles between changes, but frankly Transman’s recommendation is likely well worth the little additional cost.

I’ve been doing the half ATF change (no machine flush) and replace the filter every 15K miles! I’ve been always hesistant and uneasy to take more than 3 persons in my car (it’s a 4 door sedan, 5 seater) or drive on mountain roads, this cooler will give me the peace of mind to do these things when needed.

Just make sure you route the line out from the transmission to the trasn. cooler then into the radiator and not the other way around. It is best for your transmission to operate at the right temp. Too hot is very bad but too cool isn’t good either.

Thanks for the reminder. I already planned to add a tranny temp gauge.