Has anyone installed a block heater on a 3.9 magnum? My truck takes for ever to warm up when it's cold, my radiator is blocked off and I have to drive it for 20 minutes before the heat gets warm.

 

I like the tank-style heaters, that get plumbed into the lines to the heater core. They circulate, and warm the coolant, so, even on the coldest days, you start up your truck, and instantly have heat. The engine starts easier, warms up faster, and you don't have to freeze while the engine warms the coolant. It's already warm. Thermostat doesn't open until the engine actually gets up to temp, so, it stays fairly warm as well. By the time the thermostat opens, you already have toasty warm heat.