I have pluged mine in over night a few times, and it didn't seem to start any different than normal (and I,m sure thats the idea) also it may have helped the engine come up to temp a tiny bit sooner to get heat in the cab but it ( the block heater ) don't get the thing near operating temp so its not "warm" when you first get going and the exhaust brake helps it come up to temp a little bit sooner as well ,but in the winter even it can't keep it up to temp if you let it idle too much, the thing will drop below operating temp if you let it idle, until it goes into its own warm up mode (IE: the fast idle and engine brake ) as they cool off greatly at idle. dodge sells a winter cover for the grille and it should help keep it warm ,but I haven't tried one yet...I was told cover up more and more area untill I could hear the cooling fan cycle often and then open it up some( less fan cycle )to find the right size opening to keep heat ,but not be to closed for proper cooling??? my friend has a power joke and it acts and sounds like its sneezing when its cold ( reves up, spools turbo, then drops rpm, every min. or so) it even slobbers out the exhaust when it does it. (moisture spraying out exhaust when the revs go up)