It's been anywhere from -0 to 50. I liven in the communist republic of NJ. What do you think is proper, what the attitude is reading or dummy gauge?
02 four door dually with 142000 miles, Bills intake, 5" MBRP from down pipe back (no muffler) and Edge Juice with Attitude
When you say dummy gauge do you mean the stock gauge in the dash? I'd get your thermostat checked. I live in country that get down to -10 on occasion and I have never had any trouble getting my truck warm, and I don't use a blanket.