Those with aftermarket water temp. gauges, what are your coolent temps getting up to? I installed a Autometer water temp guage a couple of months ago and ever since the temps only get up to 180 degrees. It hit 190 a few times rollin down the interstate at 75 in high 90 degree air temps and the A/C cranked up, but thats it. That seems kinda low. What thermostat does our trucks come with?