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Discussion Starter · #1 ·
Last weekend, I did two things with my transmission.

#1 I changed the oem cooler out for a B&M supercooler

#2 I did a complete flush in the tranny going from Mobil 1 syn to Amsoil syn atf fluid.

I immediately began to get warmer temps on my gauge. My sending unit is on the return line just after the cooler. I'm reading the temp as it goes back into the tranny. My gauge really never got off of 100 degrees. Maybe 105-107 (can't be exact...analog autometer). This is with oem cooler and Mobil 1.

Anyway, after the change, the temp jumped to 120 and kinda hovered around there. Same conditions outside. This is with the Amsoil and supercooler installed.

I then pulled the supercooler and put the oem back in its original mounting location. Temps are back down to 110-115. Not all the way down, but better with the oem.

This is under no load (not towing) driving around town, stop and go along with freeway driving.

I know I broke a big rule here. Don't change more than one thing at a time!

Either way, what I'm seeing on my truck is that the Amsoil is running hotter than the Mobil 1 did. And yes, the level is correct on the dipstick. The temps are not considered major, but still significant for me to notice.

I'm going to go to the junk yard and pick up another oem tranny cooler off a truck and run two oems in series.

I don't understand why the temps went down when I pulled the supercooler off and installed the oem back. I got the supercooler for it's superior design.:beatsme:

any thoughts?


483 Posts
Check the fluid level. I wouldn't sweat on the temps, Amsoil is going to give you the protection you need.

Disconnect the battery overnight to let the TCM & ECM know you have the best soup in there.
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