My CRD sits in a heated garage so that is no issue. But every other diesel I own has not only a block heater, but an oil pan heater also. And gets plugged up at 20F or less. It is great to have a Detroit Series 60 start at 0F like it was starting in August with almost instant full oil pressure. Like was stated, unless your are on a hunting trip or somewhere you couldn't plug up, not sure why anyone would not plug up their CRD when the temps drop. Makes it a lot easier on the engine. And one could have it on a timer to conserve on the electrical side of the equation.

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Environmentalist Green + Socialist Red = Facist Brown

2006 Liberty CRD, Frankenlift II, Al's A Arms, Moog LBJ's, GDE tune, Etechno GX3123 Glow plugs, Fumoto drain valve, Elephant hose CCV mod.