[ElGracho]

Originally posted by Mike76251


This is something I have shown many people that want to add a electric fan to replace the stock one.
It still takes power to turn the electric one. In fact....it usually takes more power to turn the electric fan than to turn the stock one.

Simply put, this might make sense, but with everything taken into account, it probably doesn't. If you use a temperature activated switch for your electric fans, they will be more efficient then even a thermostatically clutched mechanical fan. This will be most true when you are driving down the road at about 30 mph or more. At the faster speeds, the air moving through the radiator just from the truck moving is more than what the fans move, and the fans can shut off.

If you never drive above 30 mph, mechanical fans will be more efficient assuming you have a good fan shroud and the fan is properly placed. This is because you don't have to convert rotational energy to electrical and back to rotational with each conversion having some inefficiencies.

As far as two batteries, if you don't need them, the second one really is just extra weight and extra cost.