Ford in-dash Inclinometer/lean gauge

I don't believe that they are accurate at all. I had a 2011 F350 and on our trip to Alaska and going down several grades that were marked as 7% grades and the most I saw on the truck gauge was 3 to 4% for the entire grade. Made no difference whether I was going up or down it just never seemed to be that accurate. Thus I would never rely on it for leveling you camper. Either bubble levels on the side or a level on the floor. The way I like to do it is level my camper one time using the round bubble in the freezer on the fridge and then I put a pair of small levels on the front drivers side corners. This way I can just step out of the cab and see how far, if any, I'm off.

If you have a Smart phone. There are APPs for that. I have one on my iPhone.

I don't find it accurate enough to be my only gauge. If it reads 0,0 you may be ok and if it reads 3,4 your in trouble but in between extremes I use a pair of bubble gauges.

By the way, I find it extremely annoying that it disappears from the instrument panel when I go to reverse.