All of the newer diesels can start unassisted at -40 pretty easily. The block heater helps with engine wear though- it takes much longer than you'd expect to build oil pressure at those temps. If you plug it in, even if it's just for an hour or two before you'd want to start the truck, the oil will flow much easier and the crank speed will be faster.


'18 Ford Raptor, random motorcycles, 1968 Plymouth Fury III - 11.37 @ 118