I filled the tank last night and was able to estimate/calculate my fuel mileage for the 300 miles I towed the empty horse trailer [2350 lbs]. Over 200m on I-75 at 65-70 mph, the rest GA two lane and four lane blacktop, 55-60 mph, rolling terrain. I've been getting 21 mph sans trailer; my combined on this tank and a half was 16.6 mpg, and my calculation of the 'towing' mileage puts it at 13.4 mpg. I expect my 'loaded' mileage, adding 2400 lbs of horse, tack, etc., to be in the 12.5 range. Your results may vary
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