Q: How far can tires legally extend outside the body of a pickup?
A: Sometimes I wonder if when I answer a question I’m unwittingly assisting someone in winning an argument. So I have my own question in response to this one: Are you asking because you want to make sure your pickup complies with the law, or because you made a bet? I’m okay with either option; I’m just curious.
Tires cannot project beyond the vehicle at all without some sort of protection. The Revised Code of Washington states, “No person may operate any motor vehicle that is not equipped with fenders, covers, flaps, or splash aprons adequate for minimizing the spray or splash of water or mud from the roadway to the rear of the vehicle.” Relying on just this rule, you might get the impression that the tire can stick out past the fender as long as there is a mud flap behind it. However, Washington Administrative Code 204-10-022 provides additional details, including the requirement that the fender cover the entire tread width of the tire.
There is a provision that allows vintage vehicles and street rods to forgo fenders or mudflaps, but only in limited situations. Unless the pickup in question is more than forty years old, worthy of being called a collector’s item and only driven on paved roads in good weather, the tires cannot extend past the fender.