Uneven Tire Pressure: Impacting Fuel Economy And Performance

Fuel economy is a key consideration when buying a car, affecting both your wallet and the environment. One often overlooked aspect that has a significant impact on fuel efficiency is the pressure of your tires. Tire pressure is the measure of the amount of air in your vehicle's tires, usually recorded in pounds per square inch (PSI). Maintaining the correct tire pressure is a simple yet vital practice. It plays a significant role in optimising fuel efficiency, potentially saving you money and reducing your carbon footprint.

Under-inflated tires can lower gas mileage

According to the U.S. Department of Energy, keeping your car tires at the recommended pressure can improve your gas mileage by up to 3%. Conversely, for every 1 PSI drop in the average pressure of all tires, under-inflated tires can lower gas mileage by about 0.2%. This can quickly add up, especially for those who drive frequently. For example, if a vehicle's tires are underinflated by 10 PSI, they could be losing up to 2% in gas mileage, which is the equivalent of paying an extra 6 cents per gallon of gas.

A study by the National Highway Traffic Safety Administration (NHTSA) in the USA found that every 1% decrease in tire pressure correlated to a 0.3% reduction in fuel economy. This means that under-inflating your tires by 10% increases fuel consumption by 2%, 20% under inflation increases fuel consumption by 4%40% under the recommended level, tire fuel consumption increases by 8%.

It is important to note that tires naturally lose 1 pound per square inch (PSI) of pressure per month, and temperature changes can also affect tire pressure. Therefore, it is recommended to check your tire pressure regularly and adjust it to the recommended PSI to ensure optimal fuel efficiency.

Recommended tire pressure

Maintaining the recommended tire pressure is crucial for several reasons. Firstly, it ensures the car handles, brakes, and operates smoothly and safely. Under-inflated tires can lead to excessive heat buildup, causing the tread to separate from the tire and potentially resulting in a blowout at high speeds. Secondly, proper tire pressure improves fuel economy by reducing rolling resistance. When tires are under-inflated, they become soft, increasing the rolling resistance between the road and the rubber. This, in turn, forces the engine to work harder, burning more fuel and increasing fuel costs. According to the U.S. Department of Energy, keeping tires at the recommended pressure can improve gas mileage by up to 3%.

It is important to distinguish between the recommended tire pressure and the maximum pressure printed on the tire's sidewall. The maximum pressure is the upper limit that the tire can safely withstand, not the optimal pressure for everyday driving. Over-inflating tires can lead to reduced traction, impaired braking, and an increased risk of dangerous blowouts. It can also cause premature wear on the center of the tire's tread and reduce its lifespan.

To check your tire pressure, use a tire pressure gauge, which can be inserted over the valve of the tire to measure the pressure in PSI. It is best to take a "cold" reading before driving or when the tire is not exposed to sun or heat, as temperature fluctuations can affect pressure. Maintaining the recommended tire pressure is a simple yet effective way to improve fuel economy, enhance safety, and extend the lifespan of your tires.

Fuel efficiency at different tire pressures

Fuel efficiency is a key consideration when purchasing a vehicle, impacting both your wallet and the environment. One often overlooked aspect that significantly impacts fuel efficiency is tyre pressure.

The U.S. Department of Energy reports that for every 1 PSI drop in pressure across all four tyres, there is a 0.2% decrease in gas mileage. This may seem negligible, but it can quickly add up, especially for those who frequently drive. For example, if your vehicle's tyres are underinflated by 10 PSI, you could be losing up to 2% in fuel efficiency, which is the equivalent of paying an extra 6 cents per gallon of fuel.

A study by the National Highway Traffic Safety Administration (NHTSA) in the USA found that every 1% decrease in tyre pressure resulted in a 0.3% reduction in fuel economy. This means that a tyre underinflated by 10% increases fuel consumption by 2%, a 20% underinflation increases consumption by 4%, and at 40% underinflation, consumption increases by 8%.

Tyres naturally lose 1 PSI of pressure per month, and temperature changes can also cause tyre pressure to fluctuate. A drop in temperature of 5°C results in a 2% loss of tyre pressure, while a rise in temperature of 5°C increases tyre pressure by 2%. Therefore, it is recommended to check your tyre pressure at least once a month and more frequently during significant weather changes.

Maintaining the correct tyre pressure is essential for optimising fuel efficiency, reducing unnecessary tyre wear, and ensuring your safety on the road. By keeping your tyres inflated at the recommended level, you can improve your gas mileage and save money.

Safety risks of under-inflated tires

Under-inflated tires can lead to a host of safety issues, which can put the driver, passengers, and other road users at risk of harm.

Firstly, under-inflated tires can cause increased friction, as more of the tire's surface comes into contact with the road. This can lead to overheating, which may result in premature wear and tear, tread separation, and, in the worst cases, blowouts. Blowouts can be extremely dangerous, as they cause drivers to lose control of their vehicles, potentially leading to crashes. Additionally, other drivers may swerve to avoid debris from a blowout, which can also cause accidents.

Secondly, under-inflated tires can make it harder to handle your vehicle, affecting your ability to stop, turn corners, and make evasive maneuvers. This can increase the likelihood of a collision or veering off the road.

Furthermore, under-inflated tires can lead to longer stopping distances, as they don't have as good a grip on the pavement for braking effectively.

Finally, under-inflated tires can cause costly vehicle damage. They put greater pressure on the suspension and chassis, risking the destruction of vital components. This includes stress on brake lines, wheels, callipers, fenders, and rotors, which can lead to expensive repairs.

To avoid these safety risks, it is important to routinely check your tire pressure and maintain the recommended level. This information can be found in the owner's manual or on a sticker in the driver's side door jamb, glove box, or fuel filler door.

Temperature's impact on tire pressure

Temperatures Impact on Tire Pressure

The temperature has a direct impact on tire pressure. As the temperature drops, tire pressure tends to decrease, and as the temperature rises, tire pressure increases. This variation can be a safety concern and can also affect fuel efficiency.

Cold Weather and Tire Pressure

During cold weather, drivers may notice a drop in tire pressure, which is a natural occurrence. For every 10°F drop in temperature, tires will lose 1-2 psi of pressure. This can cause the TPMS (tire pressure monitoring system) light to illuminate on the dashboard, indicating that the tires may be underinflated. It is important to maintain the recommended tire pressure to ensure optimal traction, handling, and durability.

Hot Weather and Tire Pressure

In hot weather, excessive heat can cause a temporary increase in tire pressure. For every 10°F increase in temperature, tires can be expected to increase by 1-2 psi. Overinflated tires can also pose safety risks, such as tire blowouts, especially during the hottest days of summer.

Impact on Fuel Efficiency

The impact of temperature on tire pressure can affect fuel efficiency. Underinflated tires due to cold weather can lead to lower fuel economy, as the engine has to work harder to move the vehicle. On the other hand, overinflated tires due to hot weather can also impact fuel efficiency negatively, although this effect may be less significant.

Maintaining Optimal Tire Pressure

To maintain optimal tire pressure, it is important to regularly check the tire pressure and adjust it according to the manufacturer's recommendations. This can be done by following these steps:

• Allow tires to cool down for several hours after driving.
• Check the manufacturer's recommended tire pressure, usually found on a sticker in the driver's side door jamb or in the owner's manual.
• Use a tire pressure gauge to measure the current tire pressure.
• If the pressure is too low or too high, add or release air as needed to reach the recommended PSI.

By maintaining proper tire pressure, drivers can ensure optimal fuel efficiency and safety on the road, regardless of the temperature fluctuations.

Frequently asked questions