When driving big truck, I had a 1500 watt block heater on my Cat 3406B (most all engines have a plug somewhere you can screw in the block heater). I also had a small circulation pump that moved the coolant through the two Arctic Foxes (pipe loop that is mounted in the fuel tank to keep the fuel warm) with one in the primary fuel tank and in the water tank that was also a 75 gal fuel tank on the outside of the truck. I always had the block heater on when the generator was on since the gen was a gasoline Onan commercial 6.5 and always wanted some kind of load on the gen. The gen lasted 12,000hrs because of this. Personally like the electric block heater over the Webasto. I never had a problem with the electric block heater. I don't think the Webasto owners can say that. Good Luck, TomC