Such cars also have rotating the tires as part of the maintenance schedule. If you rotate the tires, I don't think the difference in size will be significant.

Such cars also have rotating the tires as part of the maintenance schedule. If you rotate the tires, I don't think the difference in size will be significant. > Think of this scenario. What happens when someone sits in the back seat of a car? That compresses the rear tires slightly, imparting a slightly a different radius. The tire radius changes, but that doesn't matter. What matters is the rate at which the axle turns relative to distance covered, and I doubt that changes significantly with loading.