How Cold Can It Go?

[gophergunner]

This thought of cold starting came to me after talking with my brother. He used to work for a company in Edmonton that had a cold room and they were doing testing on some military trucks for cold starting. I believe he said down to -60 Celclius the truck would start with some help from preheaters but completely independent of outside sources of power.

So I was just curious, has GM done any testing with Duramax engines to see how cold it could get and still have them starting without even plugging them in?

I recall starting mine several times in the -35 to -40 range without having it plugged in. It was rather slow turning over but I always thought it could be colder and it would still start.

[More Power]

Yes, GM did extensive testing of the original LB7 nearly a year before the engine was released. They equipped a fleet of oil rig trucks with the Duramax on AK's North Slope over one winter. GM engineers reported that cold starts weren't a problem, but rather to get more cab heat. In response to this GM made a series of mods to help with that.

I suppose there's the possible and the practical, where cold temperature starts are concerned. You've apparently discovered the possible. From a practical standpoint, your engine, batteries and electrical system will last longer if you use the block heater below zero F. I've driven a diesel pickup at -35 F, and the truck (not necessarily the engine) wasn't all that happy... The shocks don't shock much, the heater fan makes odd noises, and I think about the gell point of diesel fuel....

Jim