How much fluid to drain and fill transmission with bigger cooler?

Hey guys, just wondering if anyone has done a drain and fill on their truck with a larger transmission cooler installed and how much fluid it took. Looks like the stock transmission is 4-5 quarts. Cooler in question is the

$185 Derale 52506 25 Row Core Stacked Plate Cooler Kit , Black

Derale 52506. Toyota ATF WS is $16/quart and don't want to be wasteful or be stuck without a usable truck if I come up short. Thanks!

 

When I did my first (of two) drain and refill(s) with the stock cooler it took about 3 quarts. After 500 miles or so I drained the fluid again and drop the pan. I cleaned up the pan, magnets and put in a new screen. Once everything was buttoned up I added 4 quarts, brought the truck up to check level temperature. Very little drained out of the check plug so I was happy. When I pulled the OEM cooler to install the Tru-Cool 4454 there was zero trans fluid spilled. Once installed I added about 3/4 of a quart of fluid. The truck was brought up to temp for a fluid level check and some fluid drained out. With the new cooler the transmission took just under 1/2 quart of additional fluid.

If you're going to do a one time drain and fill with a new cooler I would think 4 quarts should cover it. In the end the best way to check the level is by getting the transmission fluid temperature somewhere between the recommended parameters of 115°F and 130°F. Then you will know you have the right amount of fluid in a very expensive transmission.

Hope this helped.

 

Thank you! I got a 6 qt package from Amazon and sounds like that will cover it. I'll update the post when I do it so future people have an idea. It's insane because 6 qts is $60 but each individual quart averages $16 after that

 

I have a buddy that is a mechanic by trade so I'm able to get all my parts from the dealer at his price. Seems like the price was $6 a qt, but that was about two years ago when everything was affordable.

Good luck with your project!