Gauge reads 13 degrees high and don't know why. Suggestions? Thanks

 

Ain't nothing wrong with it.

The sensor reads ambient temp. So it's picking up heat from the engine and any other heat source around the truck.

 

BL54FD -

My experience is not the same as Home skillet's.

My temp reading is always within 2 or 3* of that posted on the radio, bank signs, etc. However, if I'm not moving, it sometimes does read higher than the actual temp.

In any case, if it is important to you, I would try replacing the sending unit first. Mine is on the driver's side of the truck, right behind the grill.

Good luck.