Recreational Vehicle Lpg Tank Valve/gauge problems of the 2016 Nissan Titan

Fuel tank gauge keeps bobbing back and forth, the digital range estimate is giving false readings leading to me running out of gas twice, and I get low fuel warnings even with the tank half full. At times the avg mpg would indicate between 15 and 23 mpg and the drop to 9. 5 within 30 mins.

When trying to accelerate we put the pedal to the floor and truck will not move at all for sometimes up to 5 mins and that's with us trying to get the truck to go. We have almost been hit several times and we have small children that rides in the truck. We smell fumes in the cab in which I have asthma and again small children which is dangerous to smell. Shifts hard and not always the same, either takes longer to shift or shifts quick. Very jerky when in traffic. The day we got home with the truck we heard a grinding noise when pressing on the brakes. It happens random like the no acceleration. On freeway when accelerating and slowing down back to accelerating there's a horrible lag. Our gauge doesn't match with what mikes we have left in the tank. When I go to the dealership they tell me there's no way and that I must be imaging it. This is our only vehicle and I dread putting my kids in the truck. Our lives and safety are at risk. Scared dealership will act like they checked the problems but really didn't. Consitantly having to refill def which a friend said it shouldn't drop that fast. Our fuel mileage has gottten worse since we had it. Dealership wouldn't cover our windshield that cracked out of no where even though we paid for that particular extra option. Dealership lied about it all including our warranty which they talked us down to this truck. Also when turning into a spot or on a street the truck makes a weird noise and the wheel only turned up to 3/4 of the way. Also when starting sometimes it takes the truck longer to start up.