It does it as soon as I start to drive it, first it seems like the temp will never heat up the all of a sudden BOOM, its at 200 degrees, then it climbs up to 245, and it stays there or a min or 2 and it goes back down to 200 and repeats itself. The truck has also been running pretty crappy lately rough idel and just not sounding right, also I have had quite a bit of white smoke on start up and idel even in 20 degree weather, could this be a blown head gasket? I had a problem with a leak a bit ago and tightened up that hose above the turbo and truck has not sucked any more collant from resivor since then. https://www.dieseltruckresource.com/...d.php?t=230383 Refrenced to last post. Im really confused.

Please help
Nick

 

still under warranty?? dealer time!

 

Please help yourself!!!!! Get it to dealer before you really mess something up if not already done. Might be nothing more than air lock in cooling system. Did you think to look at coolant level in radiator while cold??