Correct tire pressure is arguably the single most important aspect of tire maintenance. Improperly inflated tires affect everything: braking distance, cornering grip, fuel economy, ride comfort, and tread life. Despite the proliferation of tire pressure monitoring systems, every driver should know how to check and adjust their tire pressure manually. Here's your complete guide.
First, you need the right tools and information. Purchase a quality digital tire pressure gauge, as the pencil-style gauges found at gas stations are notoriously inaccurate. Your target pressure is printed on a placard located on the driver's door jamb or in your owner's manual. This is the vehicle manufacturer's recommended pressure for optimal performance, and it's the number you should follow. Do not use the maximum pressure molded into the tire sidewall, as that represents the tire's maximum capacity, not your vehicle's ideal setting.
Always check tire pressure when the tires are cold, meaning the vehicle hasn't been driven for at least three hours or has traveled less than a mile at low speed. Driving heats the air inside your tires, increasing pressure readings by several PSI and making accurate measurement impossible. The recommended pressures on your door placard are cold pressures. Morning, before your first drive, is the ideal time.
To check pressure, remove the valve cap from one tire and press the gauge firmly onto the valve stem. You should hear a brief hiss as air enters the gauge, then silence when you have a good seal. Read the display and compare to your target pressure. If the pressure is low, add air using a compressor at a gas station or a portable inflator. Add air in short bursts, checking frequently to avoid overinflation. If the pressure is too high, press the center pin on the valve stem briefly to release small amounts of air, then recheck. Repeat for all four tires and don't forget the spare.
How often should you check? Once a month is the minimum recommendation, but checking every two weeks during extreme temperature swings in fall and spring is better. Temperature changes of 10 degrees Fahrenheit can alter tire pressure by about one PSI, so seasonal transitions require more frequent attention. Your TPMS only alerts you when pressure drops about 25 percent below the recommendation, which is severely low, so don't rely on it as your primary monitoring system. Make tire pressure checks a habit, and you'll enjoy better fuel economy, longer tire life, and safer driving. It only takes five minutes and the payoff is enormous. If you find your tires are consistently losing pressure, it's time to investigate for slow leaks or consider new tires from Ship.Tires before a minor issue becomes a roadside emergency.