Here's how the California Vehicle Code defines the term: "Gross vehicle weight rating" means the weight specified by the manufacturer as the loaded weight of a single vehicle. Each SUV maker provides this estimate of how much the vehicle weighs when loaded with passengers and cargo.

Some big SUV makers also list the so-called curb weight, or unloaded weight, which is often slightly less than 6,000 pounds. I suspect SUV drivers will argue it's the curb weight that should count when enforcing the law. But they're wrong.

Not only are the California restrictions based on a vehicle's gross weight (of which the GVWR is the manufacturer's own best estimate), but the IRS grants its tax exemptions based on the GVWR. If it's heavy enough for a tax break, it's heavy enough to stay off my street.