So your vehicle’s been sitting for a while…you get in it, start the engine and pull out of the driveway when you notice a hard, rough (but very regular) vibration that only gets worse with speed. It doesn’t feel like it’s coming from the driveline or suspension – so what is it?
It could be that the tires have developed flat spots.
With the weight of the vehicle pressing down on the tires for long periods, a section of the rubber and belts can become softer (or harder) than the rest of the tire. This can be exacerbated by cold weather, or just by parking on a cold concrete floor.
Low-profile tires with short sidewalls can be more prone to flat-spotting, as can tires with an H or higher speed rating. In most cases, you can j ...[more]
Driving around on underinflated tires is just a bad idea all the way around. Underinflated tires increase a car’s rolling resistance, meaning a drop in fuel efficiency since it takes more energy to move the vehicle down the road.
A single tire that’s down by ten pounds of air means a 3.3 percent drop in fuel economy…multiply that by all four tires, and you can figure on giving up ten percent of your gas mileage. The added friction and rolling resistance also means more heat is generated, and heat is the enemy of the internal structure of a tire. That heat will damage a tire to the point of failure. Studies show that underinflated tires are a full 25 percent more likely to fail, and at least half of one-car accidents involve a tire problem as a factor. And still, it’s estimated ...[more]