I have noticed this also, and no, it's not like this on all cars.. my Vibe and my Vue were both right on. Yes, I could put larger tires on the rear, but won't that also increase the rolling resistance and hurt the mpg? Although, the MPG i have been figuring is not right, it's actually lower. Much more math needs to be involved in figuring this out... for every 100 miles the odometer says you've driven, you've really driven 97.14 miles. (approx.) will have to do more testing with GPS on next tank.
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