Tire pressure refers to the amount of air in a tire and is measured in pounds per square inch (PSI). Tire pressure affects the shape, performance, safety, and long-term durability of your tires. Underinflated and overinflated tires may negatively impact your vehicle's handling and safety, increasing the likelihood of accidents. Regularly checking tire pressure with a tire gauge and maintaining proper inflation levels extends tire life and keeps your vehicle performing at its best.

What is Tire Pressure and How Does It Affect My Vehicle?

The term "tire pressure" is a reference to the air volume within a tire, measured in pounds per square inch (PSI). It influences load capacity, tread contact with the road, and tire heat. Because tire pressure impacts tire performance and durability, it directly affects vehicle handling, safety, and fuel efficiency.

As a general rule, it's recommended to check your tire pressure at least once a month. You should also check tire pressure before heading out on a long trip or before traveling with a heavy load. One should follow vehicle manufacturer-recommended tire pressure specifications because your vehicle runs best when your tires meet the parameters set by manufacturer engineers. The correct tire pressure specs can be found on your driver's door jamb sticker, in your owner's manual, and via online manuals specific to your vehicle.

Vehicles manufactured in 2008 and newer come standard with tire pressure monitoring systems, and these systems trigger when tire pressure is critically low. Operating with a tire with pressure below the pressure recommended in your owner's manual is not optimal. Make sure to check your owner's manual for the recommended tire pressure specific to your vehicle, as it indicates the tire pressure to help maintain optimal vehicle performance. Routine tire pressure inspection is still the safest approach that helps ensure optimal tire wear and performance.

How Do Underinflated Tires Affect My Vehicle?

An underinflated tire has a tire pressure that is below recommended specifications outlined in your owner's manual. Low tire pressure diminishes vehicle stability, handling and braking. It also increases fuel consumption, worsens tread wear, and heightens the risk of a blowout.

Remember to check your owner's manual for the optimal tire size and tire load index for your vehicle. Your tires should be rigid enough to support your vehicle's weight, especially during turns and braking. But when they're underinflated, they lose that necessary rigidity. This may not only affect their ability to support your vehicle's weight but may also hamper their capacity to keep your car stable during cornering and braking. This is because underinflated tires flex more than they should, which may compromise your vehicle's stability in these crucial situations.

Additionally, underinflated tires have softer sidewalls that yield a larger contact patch, increasing rolling resistance which means your engine needs to work harder to get your vehicle moving, resulting in increased fuel consumption.

Tire pressure maintains the shape of your tires, ensuring optimal contact with the road. Underinflated tires deform, causing their sidewalls to come in contact with the road surface. This contact prematurely wears the tire's sidewalls and degrades the structural integrity of the tire, since sidewalls are not designed to withstand heat and friction. Exposing tires' sidewalls to heat and friction wears them down, increasing the tire failure risk.

A dangerous combination of diminished sidewalls, increased tire load, and high heat generated from high-speed road contact may damage the structure of your tires, leading to a blowout.

How Do Overinflated Tires Affect My Vehicle?

An overinflated tire is generally considered to be a tire that has a tire pressure that is over 10% higher than manufacturer-recommended specifications. This creates additional pressure on the tire's sidewalls, which may diminish traction, worsen suspension performance, increase suspension and tire wear, and increase the risk of a tire blowout.

Overinflated tires expand beyond their intended shape, reducing road contact surface and resulting in reduced grip, slower acceleration, and longer braking distances.

Overinflated tires wear out faster because the weight of your vehicle, plus the tire-to-road friction is isolated to a smaller road contact patch.

Excess air pressure also limits the tire's ability to absorb road vibrations and shocks, leading to a rougher ride and potentially increasing wear on your vehicle's suspension system.

There may be a higher chance for potholes and sharp objects to puncture overinflated tires because excess air pressure leaves little room for your tires to compress and cushion an impact, which can cause them to blow out.

How To Check Your Tire Pressure

It's best practice to measure tire pressure before driving or 3 hours after driving. This ensures that your tires (as well as the air inside) are cool and that you get an accurate reading.

The tire pressure of a vehicle may be checked by using an accurate tire pressure gauge in four steps:

1. Remove the tire valve cap.
2. Insert the tire pressure valve into the valve stem; a hissing noise results.
3. When the hissing stops, note the reading.
4. Repeat the process for the rest of your tires, including your spare tire.

How To Put Air In Your Tire

If your tires are underinflated, adjust the pressure to the manufacturer's specifications. You have a few options: visit the dealership, stop by a gas station, or you may inflate them yourself with a portable tire inflator.

Dealerships typically offer comprehensive maintenance and can ensure your tires are correctly inflated along with other tasks. Their technicians are well-versed in the appropriate tire pressure for your vehicle.

At a gas station, you can either request assistance from an attendant or do it yourself. Many gas stations have air pumps customers can use for free while other gas stations charge a small fee. Using a gas station pump generally involves setting the air pump to the desired pressure at the terminal, removing the valve stems from your tires, and inflating your tires. The pump will automatically stop when the target pressure is reached. The same process applies if you're using a portable inflator. It's important to note that available air pumps may vary between gas stations. While the process for inflating your tires is straightforward, make sure to follow the instructions printed on the air pump you're using.

If your tires have too much air, release some by opening the valve stem. Regular pressure checks are essential for maintaining optimal performance. Should you release too much air, simply add more to meet the recommended specifications.

Seasonal and Regional Considerations

Seasonal temperature fluctuations affect the air inside your tires. Hot temperatures cause air molecules to expand, increasing tire pressure. In contrast, cold temperatures cause air molecules to compress, decreasing tire pressure. On top of routine tire inspections, it's important to account for temperature fluctuations.

By way of example, if your tire pressure is currently at 32 PSI, and the temperature drops by 50°F, your tire pressure may drop by several PSI while they are cold. The inverse is also true for when the temperature increases. Make sure to account for changes in temperature by checking your tire pressure whenever seasons shift and by adjusting tire pressure to account for these temperature shifts.