As a kid in the 80's I asked my dad what mileage motorhomes get.
He just said that they all get about the same as his 1965 Lincoln Continental or his 71 Mk IIIs, (he used to restore/collect/sell them, over a dozen of them). About 6mpg on a good day, maybe up to 9mpg depending on if they are going downhill, and have a good backwind.
And then there is the universal sarcastic motorhome MPG answer: "If you have to ask, you probably should not own one".
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