Was waiting in line at a drive-thru over the 4th holiday and noticed the trucks temp gauge climbed well over 220F! (avg coolant reading is 190F). I was only idling at the drive-thru for about 20 minutes & cant figure out why I'd see the coolant temp jump to over 220F ... especially at night with outside air temps at only 78F!?

 

...yeah, that seems odd. Could you tell if your fan clutch kicked in (loud whooshing noise like a jet engine, pulls RPMs down a tad IIRC) ? Other than that you may want to flush and fill the coolant, you may have a bubble somewhere. Also, next time drop it into neutral. Your torque converter may be heating up in drive with the brakes on, but that shouldn't effect engine temps (except for the tranny cooler is in front of the radiator).

 

Don't really recall the tell tail woosh of air from the fan clutch engaging since I was lost in conversation with a group of friends in the truck. Should've dropped it into neutral for sure but kept thinking we weren't going to be stuck at the drive-thru quite that long. Once I was back on the road, I cranked the heat and temps returned back to norm w/in 5 min and haven't had any issues since. Just trying to figure out if something's about to give up the ghost and leave me stranded.

 

When the engine is cold, pull the radiator cap and check your antifreeze level. It sounds like it is low on coolant.