I quit checking actual mpg about 3 years ago. I have not had a problem since
I still have to fill up before every trip. Does not matter is genny runs the entire trip or not, I have to fill up again as I approach 1/4 tank, or if I see a really good bargain on gas. Last time I bought gas it was $3.32/gallon. I couldn't tell you how many gallons I bought, I didn't care; but I promise you I filled it up 101% of capacity. I drive 70 mph because that is what I view as the safest. I have fewer trucks passing me and I can overtake slow drivers and RVs with ease.