Like others have more or less said, to be that nit picky is a waste of resources for a dealer, and just drive up the cost of business for GM and in turn that gets passed onto us consumers. I've compared my speedometer to my GPS on a Garmin, and my phone, and it is spot on accurate. If I change my seating position, my perception of the needle changes slightly. This is the same effect as if your'e in the passenger seat looking at the fuel gauge. (Or any of the gauges for that matter.) It will look like a different reading than when you're the driver because of the angle in which you're viewing it...