Howdy,

I just intalled a transmission temp gauge on my 93 f250.
Now I would like to know what the highest safe temp is, before it starts melting down?

Thanks
Gr8ride

 

Fom reading a chart in a shop and from my vague memory...

You want to be between 150 and about 190. Supposedly for every 10 degrees above 190, you cut tranny life I think by a third or even half. When you get up around 250plus, you are counting life in just hundreds of miles.

You also don't want to run too cold(I. E. don't get the biggest horking cooler you can find) The newer trannies appear to have a temperature where they want to run.

I think there is a sensor inside that delays shifts when cold. My three vehicles, 94-96 all run at a higher RPM when first run in the morning. they run at that RPM for about 3 miles and then they drop down to their normal warm cruising RPM shift points. I am no expert and am just guessing that this is the case for all new trannies. I have also read this to be true. A big cooler will delay warm up and prevent you from getting best performance from your rig in cold weather.

The tranny shops I have used in the past all recommended a cooler that was at about the gross max rate you expected to have. For example if your truck and trailer weigh a total of 16,000 pounds use a cooler around that, don't go for the 32,000 pound cooler.

Good Luck,

Jim Henderson

 

Thanks for the reply Jim.
I chose the cooler I am running now by the max GVWR just as you suggested.

Thanks again
Gr8ride