In the summer my truck runs 195, in the winter 190, below -5 though it won't get above 186 if I'm moving. That is unless I put cardboard in front, brings it back to 195. It will hit 195 at idle even below zero. When its moving is another story. Also check your door seals, I had a bad leak and blamed the poor heater. Well heater still wasn't good but fixing that seal helped a lot.

 

Also, be sure to get a Stant SuperStat. It's a very well made thermostat and I've never had any issue with them.