I thought the same thing in ‘05 Safari with C9. The mechanic at Sacramento Truck told me there are two sensors. He heated it up to verify dash gauge is working though far behind the Alladin reading. The reading temps eventually are the same. I’ve seen the dash gauge go up on long hill climbs since then, otherwise in normal driving it doesn’t move. I watch the Alladin screen in these hill climb situations because the dash engine temp gauge climbs into the high range and alarm starts to buzz while the Alladin will show temperature increase, though still ok. I was told the gauges used are not so accurate compared to the Alladin readings.
I tow a F150 crew cab.