When the mercury dropped to 10-below this morning, I pondered the age-old question... "Can I use fuel additives in my fuel without screwing up the warranty or anything else on my Duramax?"

I called the service tech at the dealership what sold me the truck up in Montana. "I'm not aware of any restrictions on using non-alcohol based fuel additives." was the reply.

I then spoke with the tech fella over at Red Line and got the same answer.

My owners manual sidesteps the issue completely. In the "extreme cold weather operation" section, it says "If the fuel gels, take the vehicle to a warm area to thaw." Real helpful.

My plans are to use Red Line 85Plus (Winter Blend) from now until the daisys bloom in the Spring.