The factory service manual (FSM) covers this. Once you install the cooler you need to park the truck on flat ground and open up the fill plug on the transmission pan. If fluid comes out you are over filled. If no fluid comes out you need to add more.
I would suggest that you add 1-2 quarts when installing the cooler then open the fill plug and let out the extra.
Once you have this all done you need to drive it for a day or at least up to 175°F (aka operating temperature) then recheck the fluid level.
You can get the fluid from the dealer. Toyota P/N 00289-ATFWS (WS is 'world standard').
Wow so much bad info above. Follow the manual procedure above, its not difficult.
The temp at which you open the hex head drain is 106*-113*F.
On your install, I would orient the nipples either down or to the side. Use the lower nipple as the return to the transmission. This allows the fluid to drain back to the transmission. Why is this important? During very cold days, the atf wont gel in the cooler and block flow or create back pressure.
I went full Amsoil synthetic so Im not worried about the fluid getting too cool, but my transmission only gets up to about 135* now with my cooler installed.
Just curious about your comment, "Wow so much bad info above", could you be more specific and clarify so the OP can know what you referring too, I know there is a bit of bad info posted but I wouldn't say "...so much...", it seems that you're saying all the info posted before you posted is bad info?
Wow so much bad info above. Follow the manual procedure above, its not difficult.
The temp at which you open the hex head drain is 106*-113*F.
On your install, I would orient the nipples either down or to the side. Use the lower nipple as the return to the transmission. This allows the fluid to drain back to the transmission. Why is this important? During very cold days, the atf wont gel in the cooler and block flow or create back pressure.
I went full Amsoil synthetic so Im not worried about the fluid getting too cool, but my transmission only gets up to about 135* now with my cooler installed.
You're calling out others for bad info but the info you gave about orienting the nipples is totally wrong. The nipples go up or to the side. And if you mount it with them on the side the lower nipple is the inlet to the cooler, not the return to the transmission.
Actually, inlet (HOT) is up top, and return (COLD) is on the bottom. This is the principle radiators. As fluid cools it condenses and settles. If the nipples are top, it doesn't really matter.
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Actually, inlet (HOT) is up top, and return (COLD) is on the bottom. This is the principle radiators. As fluid cools it condenses and settles. If the nipples are top, it doesn't really matter.
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