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Trying get data on operating temperatures on everyone’s transmissions. Please let me know weight of vehicle , type of transmission, manual or sequential, ambient temp, if you have an oil cooler, what type of cooler, and size. Been searching a bunch and feel like there is a real lack of credible info. Thanks for your efforts!!! I’m also intere


Well-Known Member
just did 6 speed auto dodge 6.7 diesel, towing on 298K miles trans got to first summit at 255f and a week later in traffic with weekend warrior and not moving or slow got to 279f.
Had trans replaced and turned by Jasper and dyno tuned and now 170f with trailer and at speed. Fluid was burnt in old trans

Dave Cole 4454

Well-Known Member
At 230 sustained, im concerned, over 240 im driving the gauges.

Normally operates at or lower than engine temp. If its cool outside I need to turn fans off to keep it at 160.

Thats pan temp. We measure pump temp at over 300.

This is on a Reid Case built TH400
Depends upon where you take the temp from. On the in(pan side) you can run 300 all day long with good fluids. Now the Converter temp should never go over 400 or you risk going up in flames. So many people get scared of trans temps. A really good fluid such as an Amsoil super shift racing atf(recommended by coan) can handle 400 degrees without an issue for an extended amount of time without breaking down. It is the seal around the converter snout/input shaft that will fail.