About engine temperatures, for last generation the cluster gauges are so-called "dummies".
They are computer-controlled to show steady values, so consumers don't jump the gun observing temp or oil pressure variations.
The program keeps the needle steady till something extreme happens.
That might be why so many 6l Powerstrokes got replaced since with oil cooler, or EGR cooler clogs - the coolant gets boil over, when the gauge will not show the problem unless 1/2 of the coolant is already behind the truck.(ask me how I know?)
I was really pleased to notice that my 2017 F350 beside dummy gauge, has digital display that appears with accurate temperature once the engine goes over 185F (?)