Week before last the thermostat never opened and the truck overheated. Tried to baby the truck to work but to no avail. Ended up taking the thermostat out on the side of the road (-10F) and after putting everything back together, thermostat opened. 2 days later w/ new thermostat same thing, but eventually opened on own before I got the check engine light. What would cause this?:bang: Also, @ both of these times the in cab heater never kicked on the whole 20+ miles to town. Are these things coincidence or are they linked together? Sorry for the long post. Thanks.