I've got an 84 K5 with a new remanufactured engine and I've noticed something that seems a little strange happening. It's been pretty cold here lately and I always make sure to let my truck warm up for 10 minutes or so before taking it out. Then when I am driving down the road I notice my temperature gauge doesnt really stay settled in one place. As I'm driving the temperature will shift from like 185 to almost 205 or so... I know that those temperatures are not anything bad but I was just wondering what was causing this. And it doesnt just happen when the engine is still warming up it is all the way through the drive. Anything I should be concerned about? Maybe a new thermostat? Thanks for the help.