If you live in a cold climate and park your truck away from any electric power, and want to run your block heater a bit for sure winter startups, the Coleman Pulse 1850 generator works great. I measured the resistance of my block heater circuit and used ohms law to determine the current draw to be 11 amps, and the 1850 will do that fine. It also puts out 15 amps of 12V DC and comes with battery cables so not only will it run the block heater, but will charge up the batteries a bit too at the same time. In about 2 hours you are warmed up and ready to go. The 1850 sells for about $500 new at stores, but I found mine on e-bay new in the box for $300. It can be used for other things too such as camping or for power outages at home so I thought it was a good write-off investment.
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