Hey everyone,

I have a 1999 4x4 Supercab, 4.6L, 4R70W tranny. It doesn't have a stock towing package, but i have installed the hitch, trailer harness w/elec brake, and have installed the tranny cooler on the top transmission line off the radiator. My question, is this the return line to the transmission or is it from the tranny to the radiator line? Does it need to be installed at the bottom connection point? It seems to be alot hotter then my previous chevy as far as temperature of cooler; so i may be cooling the fluid on the wrong side of the radiator. Anyone who can shed light on it, is appreciated.

 

You are cooling it as it enters the radiator. Thus, you are not getting the fluid any lower in temperature than the coolant in the radiator. It would have been better to put in on the bottom line. That returns cooled fluid to the tranny.

 

Hey Tiger,

THanks for the reply. Are you positive about the direction of flow? I went with what i thought at the time, but since it was alot hotter then my chevy's trannycooler; i had to question it. If it's definately on backwards, i'll change it in the morning.

Thanks again.

 

I am positive. Others have confirmed it and my personal test was on a cool day while towing a 3000 lb boat, I stopped the truck and climbed underneath and felt both tubes where they pass under the radiator. The line coming from the lower outlet was substantially warmer. I would say at least 20 to 30 degrees.

Even on the outlet line as mine is , I still get a little heat off the return line. It only drops the temp about 20 degrees on a warm day. I was very suprised at how much air the fan pulls through the cooler even though it is off center from the rad and about 3 inches forward of the rad. Also, the air passing through gets about a 30 degree rise in temp.

Did you cut the line or were you able to find fittings? I had to cut mine. Make sure those hose clamps are tight! I want to change my fluid but would like to wait until I can find a new pan with a drain plug. B&M has a nice win with fins and extra 3qt capacity. Unfortunately I have a hard time justifing $200 for a new pan.

 

THanks Tiger,

I'm in the process of changing it as soon as it cools enough to change. I appreciate all your help. As far as cutting the line? No i couldn't find fittings either, so i just worked the braided rubber hose over the flared tubing end of the transmission line and then used double hose clamps on it. THat way, if i ever find them, i can change it back or remove the tranny cooler. Besides, if i ever developed a leak on the road/trail; i would be able to re-install the tranny line and not be stranded.

Thanks again.