During the trips to AZ, it was opportune times to calculate mpg. .. Didn't have an exact weight and can't take into account for high winds. This was not in controlled "scientific" conditions. So take all of the estimates with a grain of salt.
@ 75-80mph on flats, we were averaging roughly 15mpg. During one particular stretch with alot of uphills with a 1/4 tank refill between intervals, it was as low as 11mpg.
@ 65mph on flats, we were averaging better at almost 18-19mpg.
@ 55mph (rare) on flats, our best guess was 22+ mpg.
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