Originally Posted by VQ35DE
Are you talking about the wind-chill or actual temp there in IL ?
A 50%/50% mix of coolant and water is good down to -34 F. That's actual ambient temperature, not the wind-chill.
Yes, that was the actual temperature... the wind chill was around -35°F. But the actual temp dropped to -17°F.
I read the manual and it said the coolant is good until -35°F or so. But the hydrometer showed it was good to -25°F... but the next temperature down was -40°F so maybe -35° is the limit. The hydrometer might not have been that accurate.