How do they measure tires?
Ever wonder why your brand new 33x12.50s measure out to be 32x10.50? On the width, they measure at the widest part, so the tread might only be 10.5" wide, but if you include the sidewall its more like 12.5". Same with the tire height, its measure at the tallest point, so if you inflate the tire to max pressure, without it on a vehicle and measure it dead center where it's ballooned, it would be 33 instead of 32. This is really the only accurate way to measure tires, as weight of vehicle and air pressure will also affect this measurement.
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