tru cool 40,000 is doing a very great job so far and i'v installed it on 3 trucks till now no complaints, BUT when the temps are low the tranny oil temp keeps still under 130f (55c)
is it bad to run the truck hard under that tempreture? or run it even in lower?
how low is danger on the tranny??

 

I think statistically you want 150f. I'll monitor mine some time to see where it runs at. When I first leave the house my converter won't lock until the trans temps come up.

BTW The 40k has an internal thermal bypass to help it get up to temps. Do you run yours through the radiator first or just the cooler by itself?

 

Last night with 41 degree air, mine ran 113 to 125 depending on traffic. So I'm gonna say you will be fine with what you're running. The question was brought up here a while back and I think Vince answered it. I'll see if I can find it.

 

I'd like to know this too..

 

Here was a reply to a similar question that Vince B answered.
https://www.performancetrucks.net/fo...62&postcount=4

 

If it helps with the discussion at all, my Olds ate the 200R4 twice when it was my only vehicle and I was driving it over the winter, with the 11 to 1 455... But that trans was running so cold it wouldn't even move the needle on the analog trans temp gauge.

 

For what its worth, I went back and looked at 3 of my fastest passes in HPT. The starting line temps for my tranny were 95, 91 and 118 degrees. The 118 degree pass was a second pass I made and the others were the first passes I made for that day. Trans temps never went up more than 5 degrees during the passes but temps went up to the 140 range on the return road. My trans has always ran that cool and lasted over 2 years at those temps. It has only failed once, and that was burnt clutch packs while dyno testing. Trans temps when it burned up were in the 120-128 range.

 

It needs some heat IMO,I like mine around 150-175 degrees personally.

 

mine runs 135-175 depending how hard im beating on it. i think your fine, my 60e out lasted a buddys who had a stock truck that ran at 190-200 all the time.

 

I personally think that between 120-150 is a good range. Its warm enough for the TCC to operate properly and plenty cool enouh to help the frictions work well without slipping. The hotter the fluid gets, the easier it becomes to make a clutch slip.