A friend of mine is one of those businessmen who pinches every nickel so hard it turns into a dime. But he’s also smart—and safety minded.
Every fall he has his employees pull out a quarter to check their vehicles’ tires.
If a quarter is placed upside down in the center tread and the top of President Washington’s head touches the tread, the tires are swapped out for new ones. A full set.
“It’s actually a valid way to check a tire’s wear,” says Roy Benson, owner of Eugene Tire Factory & Automotive Repair. “The distance from the edge of a quarter to the top of Washington’s head is about 4/32-inch, which is the threshold where tire performance goes from acceptable to questionable.”
The Oregon tire dealer who has been in the tire business for more than three decades says, “When you use a penny to do the same check, Lincoln’s head is about 2/32-inch from the edge, and if the tread level is down to that point the tire is legally worn out.”
Tire performance studies, like those done by Tire Rack, show that braking, cornering, and overall tire performance drastically changes for the worst in those last 32nds of an inch.
“A better tool for the commercial fleet owner is a tread-depth gauge,” recommends Benson. “It costs a lot more than a quarter. But it’s also very accurate and a fleet manager can use it monitor a vehicle’s tire wear from oil change to oil change.”
So when the fall leaves start piling up on the road, take a couple minutes to see if the change in seasons is also time to change to new tires.