OldIHC

Looks like a nice truck!

When it reads hot, take the cap off (be carefull not to get burned by a sudden release of pressure/steam) and stick a thermometer in the top tank. you can use a known good mechanical, your wifes (or your) meat thermometer or any other known to be accurate thermometer. If it reads about 180 then both the truck and IR are off, and the engine is fine. Work on the truck's gauge. I don't trust IR meters, many do, but I have had bad experiences where they were way off, spent a lot of time chasing my own tail.

Two things, one, you can go up in picture size to about 500 Kib and two, it is possible that your temp sender could be going. If you can CAREFULLY remove it(use a socket not a wrench) it might have build up on it that can be cleaned off and perhaps give a more accurate reading. just a thought.

I use the US brand not the Chinese IR gun. It works great. I use it to check for a "hot wheel" (brakes aren't releasing), radiator and general cooling system temps, bad spots in wiring and fuseboxes, battery-killing draws (that one circuit is hotter than ambient temp), etc.
It's AWESOME.
I would not hesitate to trust it. Of course I take twenty measurements...you can't bounce it off shiny metal. It likes dark, non-reflective stuff.

Thanks for the information. The truck is really solid and everything works got it in May of this year and had to replace the windshield, breaks and Master cylinder, speedometer cable, just buffed out the paint and redid the interior ourselves. We are happy with the results and even happier that it is on the road now.

Is the fan shroud in place? Could run warm without it. Just a thought. Sounds like you need to determine for sure that it is actually running hot also.
Dennis

Yes the shroud is installed and your right about finding out if it is actually running hot or not. Thanks

I've drained some of the coolant from the block drain plug topped up with new tock the truck for a good hour drive and the gauge is now at the 3/4 point when I got back home the block temp was 185 f. Will keep an eye on it and hopefully it will stay like this. Thank you all for the information and tips.

I do not remember if those engine cooling systems were pressurised. I don't need to know, I am curious, that is all.

4 lbs cap on the sd-bd with one of the aluminum radiators, runs 175