Lincoln loses to Washington in new test for tire-tread depth

Buried deep in a press release from Tire Rack is a bombshell. No longer is the Lincoln-head penny the true test for replacing your tires. It will now be known as the Washington-head quarter test.

For as long as we can remember, we were taught that when you could see the top of Lincoln's head on a penny stuck in your tire tread, it was time for new rubber. That's about 2/32 of an inch. Tire Rack did some tests, with an eye-opening video, on what the difference is between a new tire (10/32 of an inch), a worn tire (4/32) and a completely worn-out tire (2/32).

The control car stopped at 195.2 feet with new tires in the rain. The next test used the same car, but the treads were worn to 4/32 of an inch, about the distance between the top of a quarter and Washington's head. That car took an additional 95 feet to stop on the slick track.

At 2/32 of an inch of tread (the Lincoln-penny test), the car skidded to a stop at a lengthy 378.8 feet, almost 90 feet more than the Washington-quarter tires and 183.6 feet farther than new tires. Maybe more importantly, the last car was still traveling at 44 mph when the Washington-quarter test car stopped.

We're all for car control here at AutoWeek. Now, if Dutch will let us borrow a quarter, we'll be off to check the fleet.

Watch the video here.

Full release below:

SUMMER ROAD WARRIOR TIPS FROM TIRERACK.COM

America's Largest ‘Personal Shoe-Shopper' For Your Vehicle Reminds Consumers How To Save Money, Think Safe and Get ‘Summer Ready'

SOUTH BEND, Ind. (May 23, 2011) – Recovering from the past few years of ‘staycations,' Americans are ready to travel again, but rising gas prices have many concerned about using their favorite mode of transportation. Experts at Tire Rack, America's largest independent tire tester and consumer-direct source for tires, performance parts and accessories, remind drivers of simple steps they can take before hitting the road to save money, think safe and get ‘summer ready'.

Memorial Day marks the beginning of the summer travel season, and this year, 59 percent of Americans plan to take a vacation, according to a survey conducted by the American Express Spending & Saving Tracker. However, high gas prices are forcing many drivers to think twice about summer road tripping.

“Most northern drivers are extremely careful during the winter on snow and ice, but the same care and caution should be applied by all drivers in summer as well,'” said Matt Edmonds, vice president, Tire Rack. “Preparing for summer travel and following a simple maintenance routine can save consumers hundreds of dollars and keep them safe on the road.”

Don't let the cost of gas and unforeseen dangers on the road keep you from your search of sun, sand and relaxation this year. Experts at Tire Rack offer the following tips for summer driving:

Save Money with Your Tires

• Pressure: Tires don't carry the weight of your vehicle, the air pressure inside them does. Underinflated tires offer less traction, reduce fuel mileage, wear out prematurely and can suffer unnoticeable damage that compromises their performance and safety. One out of four vehicles on the road is running on underinflated tires. Check tire pressure often, don't just “set it and forget it.” For a list of high-quality tire gauges from TireRack.com, visit www.tirerack.com/accessories.

• Eco-Friendly Tires: Consider purchasing low-rolling resistance tires. Low-rolling resistance tires reduce gas consumption by four to seven percent by minimizing wasted energy as your car is in motion. To learn more about eco-friendly tires, view a short testing video here: www.tirerack.com/videos/index.jsp?video=66&tab=tires.

Think Safe On the Road

• Construction Hazards: More than 25 percent of deaths on U.S. roads involve hitting a hazard along the roadside, not another vehicle, according to the Insurance Institute for Highway Safety. Slow down and be extra aware in construction areas, around maintenance crews and whenever you come upon an emergency vehicle or any other vehicle on the side of the road.

• Avoid Potholes: Driving through just one “large” pothole can weaken a tire, reducing its long-term durability and ride quality. Potholes can also knock a vehicle out of alignment, reducing handling and tire life. Drive around large puddles – they can be hiding deep, rain-filled potholes.

• Drive Through a Blowout: Instead of slamming on the brakes if a tire blows out, maintain pressure on the accelerator for an instant to preserve your car's momentum and offset the pulling. Don't hit the brakes. Once the car is stable, slowly pull to the side of the road.

Get Your Vehicle “Summer Ready”

• Don't Mix and Match: All tires are not created equal. Mixing tires of different brands, tread depths and performance categories can cause a serious loss in vehicle stability.

• Consider Summer Tires: Unlike all-season tires, summer tires are designed specifically for warm and wet weather. For a list of summer tires that deliver driving excellence in both dry and wet weather, visit www.tirerack.com/about/techcenter.jsp.

• Lincoln vs. Washington: Unexpected downpours are frequent in warm weather, and insufficient tread-depth can double stopping distance. Tire Rack has shown tires worn down to the standards of the ‘Lincoln Penny Test' can put you at risk on wet roads. Tire Rack recommends drivers consider replacing tires when they reach approximately 4/32" of remaining tread depth. Use a Washington Quarter to check tread-depth. See more here: www.tirerack.com/videos/index.jsp?video=5&tab=tires.

“Summer road trips are more enjoyable when proper preparations have been completed,” said John Rastetter, director of tire information, Tire Rack.

By Jake Lingeman