Does it really get cold enough there to need a block heater? I am in the MI Tundra and do just fine without using mine....even when its -10F out I rarely have any issues. Make sure the battery/starter/valves/glow plugs are healthy, and it should be fine unless the motor is on its last legs....but at 187k it should have 0 issues. Mine has 283k and starts up great.

I'd stick with an extension cord. Just run it out to the car only when needed. 2-3 hours of block heater should be enough to offset the cold in most situations. Just go out and plug it in a while before you leave.

Generators are pointless.....and a battery could never hope to run a block heater. (unless you used two GIANT batteries) and that would be pricey $$$ And you'd still have to recharge them, as they would likely be slow-charge and a normal drive would never get them topped off in time.

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-diesel is not just a fuel, its a way of life-
'15 GLK250 Bluetec 118k - mine - (OC-123,800)
'17 Metris(VITO!) - 37k - wifes (OC-41k)
'09 Sprinter 3500 Winnebago View - 62k (OC - 67k)
'13 ML350 Bluetec - 95k - dad's (OC-98k)
'01 SL500 - 103k(km) - dad's (OC-110,000km)
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