I have seen skid steer installs on a few of them. They do work but nothing like a regular coolant fed heater. The real downside is they do tax your charging system for sure. That 6ga seems excessive but who knows. I do know on my ford powerstroke that the glow plugs draw about 150amps on start then taper down to about 80a once they are up to temp. The big ole factory relay that looks like a starter relay continually burns up on them if you dont upgrade. But watching the voltage on the gauge plummeting just from 1 accessory is odd when you think about it. Remember headlights and starter are the 2 normal large draws, then start adding other stuff up and it gets over the alternator comfort zone quick. I generally run a coolant type heater whenever possible.

1949 GMC 150
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