HEAVY DUTY TRANS COOLER INSTALL 6.4 5R110

Sandddemon08 · Dec 14, 2013

HEAVY DUTY TRANS COOLER INSTALL 08 F-350 6.4 5R110 TRANS

A few people have asked me about my trans cooler so i figured i would just do another write up here on it, im just coping my write up from another forum

So i finally got the trans cooler i ordered last week in last night. Little bigger than i thought but should still fit were i want it under the bed. Gonna pickup the hoses today and hopefully get it done by tonight. Its a 35,000 BTU cooler rated at 4-15 GPM and a 2400 fpm built in fan, so it should help the issues i have had towing extreme loads in stop and go traffic. I'm setting the fan up with a 180 thermostat and looking to maintain less than 200 degrees under all conditions. I'll post more info when i get it done.

Sandddemon08 · Dec 14, 2013

So i was able to pick up the fittings and hose today, wifes jeep broke down so thats about all i got around to, had to pull the trans out of the jeep and tear it apart for a rebuild, by the time i got the parts for that i barley had time to get the parts for my cooler....lol always somthing....

At this point I'm going to remove the small tube from the inlet cooler line connection on the trans to the small inline filter and use those for my connection point's for the new cooler. I am matching the current cooler line size with the new install so everything is -8an or 1/2 inch. The transmission case is marked clearly IN and OUT for the cooler lines so theres no issue figuring it out which is which. I got a piece of good thermal tubing to protect the trans line where it will be near the exhaust pipe. Hopefully tomorrow after noon i can get it done and post the finished product.

Sandddemon08 · Dec 14, 2013

So i got the cooler mounted today and plumbed up,i ended up having to drop the exhaust to get it in and have a little room to work. While i was in there i rerouted my vent line on my tank cause it was spitting when i filled up. I didn't get it hooked up to the trans cause i forget to get extra trans fluid so I'll do that tomorrow. Had to weld a strap on the fitting for the fan sensor to mount it. It was a tight fit but i got it in the spot i wanted. All thats left is wiring the fan circuit, connecting hoses to the trans and adding fluid.

Sandddemon08 · Dec 14, 2013

Ok so i got the final connections completed on the trans. Took an additional 4 quarts to top the system off. Between the cooler and the mag-hytec deep pan ive added 12 quats or 3 gallons for extra fluid to the trans system.

Sandddemon08 · Dec 14, 2013

Now for the results....Before adding the cooler Towing a trailer and load weighing in at 26,000 lbs in stop and go city traffic with an ambient temp of 69 degrees i would see 217-225 degree trans temps. At traffic lights the trans would not cool off more or less maintain. On a 6% 6 mile grade traveling 40 mph the trans would go all the way to 228 degrees at about 3 miles into it before i had to back out of it and eventually pull over and let the trans cool.

After the cooler install and under the same traffic conditions the max trans temp was 198 degrees, average temp was 194 degrees. At traffic lights the trans will cool down 5-8 degrees depending how long the light is. The fans on the cooler works well turns on at about 182 degrees and turns off at about 168 degrees. On the 6% grade i was able to pull the full grade without stopping with a max trans temp of 202 degrees.

Now for the cost

DB-345-12 trans cooler (retail 552.00) mine on ebay 360.00
180 degree inline thermostat 60.00
Fittings and hoses 260.00
4 quarts motorcraft lv trans fluid 20.00

Total parts 700.00

Install time was about 7 hrs, should have been about 4 but i was having an off fabrication day....Overall i am very happy with this investment and think it will help preserve the trans considering the loads i tow.

Sandddemon08 · Dec 14, 2013

Ok wanted to add some info,originaly i added 4 quarts after i got the trans hot over 170 degrees, if you fill the trans to the hot mark with the trans you over 170 degrees when the thermostat is open you will put too much in, i had to drain some out. I took about a gallon out cause i had an issue with fluid coming out the breather on top of the trans when cold. I re-adjusted the fluid adding about 2 quarts back to the top of the cold mark when cool around 140 degrees and havent had a problem since.

Sandddemon08 · Dec 14, 2013

All who asked here is the info if you have questions let me know!

Martin #6 · Dec 16, 2013

Nice write up. Thanks. I can't really tell what's going on in the pictures of your #4 posting. In the first picture is that an external trans filter?
I think I'll forgo the thermostat and just use the upfitter switch. I already have one fan mounted cooler for the oil under the truck, but your placement allows me for another one.

JrStroker · Dec 25, 2013

Awesome write up! Good job!

ncollins64 · Dec 27, 2013

Very good write up. When I get my built trans and may do something like this also.

buck russell · Dec 28, 2013

Awesome write up!

Are you still using the stock trans pan or did you upgrade to the Mag-Hytec?

Sandddemon08 · Feb 25, 2014

Martin #6 said:
Nice write up. Thanks. I can't really tell what's going on in the pictures of your #4 posting. In the first picture is that an external trans filter?
I think I'll forgo the thermostat and just use the upfitter switch. I already have one fan mounted cooler for the oil under the truck, but your placement allows me for another one.

That is the factory external filter , my truck is a early 07 build before they changed it

Sandddemon08 · Feb 25, 2014

buck russell said:
Awesome write up!

Are you still using the stock trans pan or did you upgrade to the Mag-Hytec?

I actually did the Mag tech pan first, it was after the pan I became apparent that the pan helped keep the Trans cooler until the extra fluid got hot, once the extra fluid got hot the overall Trans took three times longer to cool.

It was that problem that lead me to the remote cooler idea.