Every spring a literal obstacle course emerges in city streets and country roads. It is a course that rewards a successful run with a smooth ride, and a poor run with wincing thumps. This is the domain of the Pothole — the enemy of every car‘s tires.
Potholes are the result of how time, water, temperature and intermittent pressures effect a road surface. While ruts appear in well-traveled dirt roads due to displacement of the dirt, paved roads exhibit missing chunks of pavement due to similar processes.

Most road surfaces are comprised of small stones welded together with asphalt that‘s been graded and rolled under pressure. This process compacts the stones and asphalt together, developing a membrane of material that holds up well to the weight of vehicles and exposure to the elements. Over time, the asphalt begins to break down, causing stones to compact in some areas while they spread apart in others. This allows for small fissures and cracks to develop, which allows water to penetrate the road surface when it rains. This water works its way down into the road surface and becomes trapped within the roadbed, sometimes penetrating through to the soil over which the road has been laid.

Enter the advent of cold weather. Rainfall quickly turns to winter ice as temperatures drop, freezing the water in the fissures and pockets within the pavement and roadbed. As winter wears on, the road maintains its strength due to the solidity of the ice frozen among the stones. But when springtime comes, beware. With warming temperatures and the thawing of water, soil beneath the pavement swells like a sponge, pushing the pavement upward. This produces holes and pockets within and under the pavement. Along comes a vehicle, exerting a ton or two of weight over the weak spot and Voila! — A pothole is born.


Potholes should be considered enemies to your car’s tires and suspension. The sudden drop and lurch of the vehicle when a pothole is encountered speaks volumes for the impact on the tire and rim, as well as the workout suffered by the car’s suspension, steering and alignment parts. The sudden jarring and twisting that occurs in rapid succession when entering into and emerging out of a pothole exerts strenuous forces that can bend metal and snap couplings.

Needless to say, the damage caused to tires presents the gravest danger from potholes. When hard stuff meets soft stuff, the hard stuff usually wins. Tires have flexibility that offer great advantages when turning corners. Yet this same flexibility allows the tire to flex upon contact with a pothole, exposing the tire’s rim to damage. Underinflated tires compound the issue, offering even less protection to the rim and risking a higher probability of tire mount failures and blowouts, or loss of vehicle control.

The tire’s sidewalls are particularly vulnerable to pothole damage. The pothole that scrapes the sidewall with 60 mile-per-hour force has great opportunity to do no good. Though the sidewalls don’t suffer wear like the tread that contacts the road, the sidewalls must nonetheless maintain their strength and integrity. Formed of thinner materials, the sidewall allows the tire to flex side-to-side. Too much flex, and the sidewall fails to maintain contact with the rim, and the tire goes flat. Not the kind of thing you want to have happen while clipping along at high speeds.

Potholes are also notorious for becoming catchalls for every loose piece of garbage and debris that can befall a roadway. More than one hapless driver has received a flat tire after a brief dip into a pothole harboring a stray hubcap, rock or sharp piece of metal. The luckiest ones emerge to drive on to their destinations. The not-so fortunate is often seen looking for a tire iron, pulled off along the side of the road.

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