John Townsend
Public Relations Manager, DC
O: (202) 481-6820 (ext. 4462108)
C: (202) 253-2171

WASHINGTON, D. C. (Monday, February 17, 2020) –– It takes longer distances to stop on wet roads and during foul weather on relatively worn tires than it does on new tires, warn the ASE certified technicians at The Tire Shop in Loudoun County. Yet the vast majority of motorists don’t know when to replace their worn tires. Compounding matters, “over a third of Americans can’t tell if their tires are bald,” surveys say. It’s a situation that “greatly increases the likelihood of a crash.” But the Presidents can help.


It’s President’s Day. It is a perfect occasion to use either the “quarter test” (which bears the image of George Washington’s head) or the “penny test” (with Abraham Lincoln’s head). The coinage will help you determine whether your tires have lost a significant amount of traction, a dangerous situation, or if your tires are “completely worn-out.” You can determine that if the top of Washington’s head is visible, or when the top of Lincoln’s head is visible. It is not as complicated as it sounds. The Washington “quarter test” is the new standard, the coin of the realm, for “measuring tire tread depth with a coin.” That is especially true for “many in the tire industry.” Here is why it is important to your safety and the safety of others on area roadways.


“The ‘quarter test’ is not only a new and improved gauge for the average motorist. It is also an early warning system of waning tread depth using the naked eye. With newer cars going longer intervals between routine maintenance at automotive service facilities, drivers may not become alerted to the fact their tires are too worn until it’s too late,” warned Greg Phillips, The Tire Shop. “Slip an upside-down quarter between your tire grooves and look at Washington’s head. If you can see all of it, it’s time to start shopping for new tires.”


To avoid “Slip sliding away,” area motorists should replace their tires once the tread depth reaches 4/32,” advises The Tire Shop in Leesburg. That’s when stopping distances have already begun to deteriorate significantly. How dangerous is it? Driving on wet roads with tires that have only 4⁄32 inch of tread depth left could increase the stopping distance of a passenger car by up to 87 feet — more than the length of a semi-trailer truck —  and reduce a driver’s ability to control a vehicle by 33%, AAA research reveals.


In other words, driving on worn tires at highway speeds in wet conditions can increase average stopping distances by a staggering 43% when compared to new tires. With nearly 800,000 crashes occurring on wet roads each year, AAA urges drivers to check tread depth, replace tires proactively, and increase following distances significantly during rainy conditions.


“Rain showers and storms can make for treacherous travel due to an unlikely suspect — tires. The only

thing keeping a vehicle on the road are four patches of rubber, each about the size of a smartphone, but many drivers fail to replace worn tires when it’s time,” said James Moore, Manager, AAA Car Care Center in Fairfax. “The Lincoln penny and the Washington quarter will let you know if you have a safe amount of tread on your tires. The less tread your tires have, the higher the probability they could hydroplane on wet roads.”

It’s slippery when wet. Tires are critical to driver safety. When in good condition, properly maintained and of the correct type and size, tires enable a vehicle to accelerate, steer and brake safely under a wide variety of road and weather conditions. Because they are responsible for much of the handling and stopping ability, tires play a critical role in the optimal performance of many vehicle safety systems.


            When shopping for new tires, drivers must take into consideration several factors such as cost, performance ratings and most importantly, when to replace worn tires. AAA conducted primary research to understand first, the performance differences between new tires and those worn to a tread depth of 4/32” in wet weather conditions and second, the performance differences between high-priced and value-priced all-season tires. Accordingly, AAA recommends:


  • Consumers begin shopping for new tires when the tread depth reaches 4/32”. Test that tread depth with a quarter.

  • Tire tread depth is measured in inch increments of 1/32”. So the critical increment for determining the safety of tires using the “quarter test” is 4/32” (pronounced four thirty-seconds of an inch or simply, 4.30 seconds of an inch). For the “penny test,” it’s 2/32” (two thirty-seconds of an inch, or simply, 2.30 seconds of an inch).

  • Keep tires properly inflated, rotate them on a regular basis and inspect them at least once a month.

  • When shopping for replacement tires, it is important to remember that the price alone is not a good indicator of better performance.

  • Research prospective tire models through consumer reviews as well as understanding tire ratings.

  • Increase following distance to allow for ample space if the vehicle ahead stops suddenly.


“Worn tires –especially bald ones –can be deadly on wet roads,” warns Consumer Reports. Yet “35 percent of American drivers don’t know when their tires are bald.Some consumers wonder whether the “quarter test” has replaced the “penny test?” Good question. Use the “quarter test” to determine whether your tires are dangerously worn, recommend AAA, Consumer Reports and The Tire Shop.  


Similarly, use the “penny test” to determine “whether your tires are worn to the point where they need to be replaced. Place a head-down penny into a major tire groove,” explains Consumer Reports. “If the top of Lincoln’s head is visible, then the tread is 2⁄32 inch, and the tire is worn out and needs to be replaced immediately. Tires also have treadwear indicators—platforms or ‘bars’ sitting inside the major grooves that become flush when the tread wears down to 2⁄32 inch.”  The coins could possibly help save your life.


But most consumers don’t understand why the standard changed and the difference between the “penny test” and the “quarter test.” Here is the rule of thumb. Tires are legally worn out when they have worn down to 2/32” of remaining tread depth, according to the law in most states. That’s when the “penny test” featuring Abe’s head comes in handy. In fact, in Virginia and Maryland it is illegal to drive on tires with less than two thirty-seconds of an inch of tread (2/32 inch). Curiously, the District has no such law. But for safety’s safe, tires should be replaced when the tread depth reaches 4/32”. That’s when the “quarter test” is essential.


AAA recently announced the acquisition of The Tire Shop, adding the award-winning auto services shop to its growing car care operations in Virginia. The Tire Shop, voted top shop in Loudoun County for 13 years including top auto repair, top inspection station and top mechanic in 2019, has one location at 925 Edwards Ferry Road NE in Leesburg. Owned by Greg Phillips and Harold Fuller, it has been in continuous operation in Leesburg for more than 35 years and has been an ASE Blue seal shop for over 15 years. 


The Tire Shop location offers 13 service bays for automotive services, including free air. The Tire Shop also performs diagnostics, brakes, batteries, oil changes and all preventative maintenance services. The acquisition of the Tire Shop brings the number of AAA car care locations in Virginia to nine as the organization continues to invest in quality automotive services.  AAA will invest in infrastructure, equipment, and showroom enhancements at the location later this year. AAA membership is not required for service. 


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AAA provides automotive, travel and insurance services to 60 million members nationwide and nearly 82,000 members in the District of Columbia.  AAA advocates for the safety and mobility of its members and has been committed to outstanding road service for more than 100 years.  The not-for-profit, fully tax-paying member organization works on behalf of motorists, who can now map a route, find local gas prices, discover discounts, book a hotel and track their roadside assistance service with the AAA Mobile app for iPhone, iPad and Android. For more information, visit

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On Tuesday, October 17, 2017, AAA and TEDx Wilmington held the first TEDx Salon dedicated to ideas worth spreading in transportation.

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