Tried looking around for something about this and had no luck. Has anyone ever put in a switch to manually run the engine fan? And if so, has it caused any problems with the fan clutch or wiring issues? Truck runs around 200 running down the road pulling about grossing 15 ton. Anytime from a stop or longer hills it's common to hit 215 easily. So as a semi tractor usually has a engine fan switch, why can't a pickup? This is on a 2003 2500, only mods are a smarty, air intake and filter, and built goerend transmission. Thanks in advance!

 

You just need to run a wire to the #1 pin on the electronic fan clutch connector and then to a switch that is grounded. Takes a little bit but it will cause the fan clutch to lock up for max cooling when needed for hills or while towing. Best to turn on before starting the climb up the hills.

 

posted here https://www.dieseltruckresource.com/...d.php?t=313766
I use heat shrink tubing and soldier the wires. never use butt connectors or scotch locks because they will always corrode and give you connection problems later.

 

Fantastic, thanks for the info.