My timer is an outdoor "swimming pool pump" type that I bought at Menards. Rated for -40F and three pronged with a rain cover. For the car I'd plug it in for an hour down to 30F, two hours down to 15F, four hours down to 0F, then six hours. All for frost plug heater and car outside all night.

A good option for us is an oil pan heater. Size of a kitchen hot pad and glued onto bottom of oil pan. Not sure of twin cities distributers, but a guy in Chetek, WI sells a good one. Heating the oil cuts the frost plug heater time in half.

I forgot: NOW is a good time to change fuel filter. Keep a spare in the trunk. Your filter will start to gel at 15F with untreated #2 so you have a month to figure out your winter fuel game plan.

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daBenz - 1970 220D