On my last recent outing With the 5ver hooked up, and pulling some of Colorado’s steeper grades like wolf creek pass that’s 9 miles and 7-9% grade with a couple hairpin switchbacks and no breaks climbing  the grade to help with cooling, my trans was creeping up to 250’ before I reached the top, ( the trans temp probe is on the output line side so I am reading the hottest temp possible as it’s just leaving the torque converter)  as I was nearly to the top I just kept going and let it cool at the summit, grossing around 19k, everything else was holding its own, but the transmission temps, and having a fresh tranny rebuild I need to try prolong the trans. life the best I can, so I figured the best way to reduce the hot output temps was to reduce the fluid temps  in the pan. 
 

So I ordered the Derale hyper cool 15960, Derale has a few coolers out there but I chose this one because of the stacked plate cooler core and  1/2” fittings and 500 CFM fan, I pared this up with the ATS deep trans pan, mostly for the built in trans temp probe in the pan and a drain plug. but it’s a beefy looking unit anyway.
I was trying to find a remote location for this cooler, and with a short bed 4x4 space was limited, and I mean really limited , most people install these behind the transfer case with the long beds but my fuel tank was not allowing that to happen, I also wanted to avoid  mounting outside of frame for obvious reasons, so I had to move it under the bed and to get away from the muffler I was damn near right above the rear axle, I also wanted to keep it mounted at a 45’ angle to help with air flow to the core, and trying not to let it hang straight down for the fear of it coming in contact with road debris, fabbing your own brackets is a necessity with these as they are just a universal fit for all vehicles, The kit only comes with 10’ of 1/2 rubber line so being far back toward the rear I had to go to the parts store and get 10 more feet to get it back to the transmission . 
 

here’s a few pics what I got so far, I do plan on keeping the temp probe on the output line just for testing to see how much the output temps reduce, then I’m  going to move it to the pan and I’m sure the temps will be reduced quite a bit, If I can regulate 210 degree in the pan towing heavy and steep I’ll be happy, tomorrow’s project is to wire the fan with an override switch to turn it off and on as I see fit,  I will update how the temps go, as I might be doing another road  trip, this time with the boat hooked to the 5ver. 

Looks good, nice job mounting it to the bed frame.   250° is cooking, it will be interesting to see what it is now during a hard pull. 

I got to test this thing out under load and I must say this cooler rocks, With everything hooked up I’m grossing 21.5k, I didn’t go over wolf creek but got to test it with some other large hills that were about 8 miles long and 5-6% plus lots of rolling hills and city driving, the hottest I have got toward the top at the steepest grade and that was 210 degree, keep in mind that I’m still probing at the output trans line so the temps in the pan are significantly cooler. Even with my engine temp creeping up to 215, the trans output seemed To be 5 degree cooler. On flat and rolling hills It maintains 160 consistently, I do run with the overdrive locked out when loaded this heavy, the city temps will creep up to 190 in stop and go traffic with 80-90 ambient temps,, 

 

I was under the impression that the cooling fan was going to be noisy but can’t even hear it, probably due to its location under the bed, I just bypassed the thermo temp switch probe it came with and have a toggle switch in the cab and I can flip it on and give the cooling a head start if I’m  coming to a big grade , 

Excellent, and thanks for the follow up.