install in front of your radiators
they are supposed to work great in slow moving traffic or stop and go traffic,
just turn on and your engine and tranny stay at a lower temp ...
They work great but the ones that go on front of the rad are not as efficient as the ones that that go on the back side and pull the air through. I have no clue why it's just what I was told when I bought mine. I relied only on the electric fan to cool my truck,(was young and fans rob horse power you know had no pulley driven fan at all. As long as I was moving i didn't need to have the fan on at all. Only stop and go traffic.
My buddy had a RS SS 427 Camaro.The thing was fast! He had no room for a regular fan so had two electrics. He could not keep the car cool on the highway . He had 456 gears so it reved on the highway. He put a 4 core rad in, still the same. When he want back to the rad shop he told the guy he goes down the highway , has his fans on and just can't keep it cool. The guy says, turn your fans off on the highway! He said it's like having a sheet of plywood in front of your rad. This made no sense to me. I guess you will flow WAY more air going down the highway than you ever will with the fans running.
The moral of the story is, if you are going to run a fan make sure you run the thermostat switch so you don't manually leave them on.
We both were running ours fans manually with no thermostat. the thermostats were a pain in the ass and never seem to work right so we just had a manual switch. Hopefully the kits out now are better than the kits they had then.
Highfly is right. Mounted in front they restrict airflow when moving. If the rotational speed of the fan doesn't produce airflow at a speed higher than incoming air then it's ineffective. Also you won't find an electric fan that will move as much air as the stock fans on the diesel trucks. My 2011 f 150 doesn't have a mechanical fan so for smaller gassers it's been figured out. But the electric fans are on the inside.
Engineers spend lots of time and money on the cooing systems of these trucks. They know what works.