(02-09-2017 )Hammerhead Wrote:  

(02-08-2017 )386lover Wrote:  Where can I find info on converting from water cooler to air? I tried some google searching and came up empty.

You've found it.
You can pull the fittings and install plugs in the head and the water pump for the coolant, or loop the lines from the head to the return if you prefer. You have to drain the coolant and refill to do this. Another nice option is install a Webasto or Espar engine heater using these lines for the coolant heater instead. Run new oil lines, which exit out the lower passenger side of the tranny through an air exchange cooler. Either use an OEM lower rad mount one, or find a place to nicely install a small hydraulic oil cooler, with a 12V thermostatically controlled fan if you like, somewhere under the truck. The backside of fuel tanks with mounting brackets off the fuel tank frame brackets is the most logical solution I've seen. I've also seen one mounted, painted, and very clean install to the lower rear of the bunk like an APU condenser.

I thought I had a cooler issue out in northern QC last fall, so I flushed the tranny twice with ATF, looped the lines, and filled it with good 75/90 to get home. I was grossing 175,000lbs, and my tranny ran at 180*, and climbed to 190-195* when pulling the big hills. I talked to some of the northern Quebec logging truck guys to see if I could find a cooler on the weekend when I was having the issue. They told me they just loop the oil lines together, no cooler. They use good 75/90 synthetic oil. They do this quite successfully hauling 100,000lbs payloads, on gravel roads. Liquid coolers cannot hold up to the conditions (vibration, banging, & jarring) so they found a solution.
If I didn't pull such big weights, I'd try running with looped lines for a while just to see what it will do.
If your cooler isn't leaking but your worried about it, and I would be because it's not if its when, just join the oil lines together from the cooler at the tranny where it's easy. Make up another short line that you can loop the tranny fittings to and experiment. If it doesn't work for you, you could very easily reconnect your cooler. If it does work, but you wanna run your cooler, you now have an emergency bypass system you can use to limp yourself home when the time actually comes, or even just if you're suspicious it's leaking, but you don't wanna take the chance.
To do this you need;
-one JIC male-male to join the hoses (JIC female ends) currently on your truck. A couple fittings to make a nice male-U-male would be very slick for older heat hardened lines.
-one hose about 18-24" long with two female 45* JIC fittings - install to loop the in/out fittings off the tranny.
-a handful of good zip-ties to route, tie, and keep hoses from flopping around.
-voila! One emergency liquid tranny cooler bypass system.

(02-12-2017 )386lover Wrote:  What size cooler would you recommend?