Park on the otherside of the area you normally do if possible.that's interesting because the parking area where I left my truck is on a hill road but would otherwise leave vehicles leaning towards the side. I parked my truck the same way tonight so I'll see tmrw if has the same effect.
I tried to siphon just a little gas for my lawn mover, I used the plastic filler tube and a 5/16 tube but I had the same problem.i tried to siphon gas out of [email protected] motorsports gen 1 when he totaled it last year. no luck. (hey, he had a full tank when he wrecked, what can i say?) theres something blocking it where the filler tube meets the gas tank.
as per the op, i know that how the truck is parked will affect the fuel guage. if on an incline (nose up) you will show more fuel than you actually do. if parked on a decline (nose down) you will show less fuel than you actually have. takes a while for it to level out. on an incline, your fuel will drop substantially and you dte will drop. on a decline your dte will show less, but it wont adjust. it will just say you have 100 miles to empty for 10 miles before it changes to 99 miles to empty. what i have seen is once the truck sits for a while, (most likely when the truck sleeps) it will reset itself to the current position of the truck.
I got mine from Ford, right at that parts counter.I been searching for a locking gas cap since day one when I got my 2017 Raptor, no luck at all. I still remember the gas shortage back in the 70's when everyone and the mother's out stealing gas. If anyone knows of a locking gas cap that is available for the Raptor let me know.