Check your tyres - Why correct tyre pressure is important

Written by Daily Fix - Published 04-May-2023, last updated 17-Jul-2023

Tyre pressure is one of the most important factors affecting the safety and performance of your vehicle. When your tyres are not inflated to the correct pressure, it can lead to a number of problems, including:

Reduced fuel efficiency

Underinflated tyres can increase your fuel consumption by up to 5%. This is because the tyre has to work harder to maintain contact with the road surface, which requires more energy from the engine. So for the best fuel economy, make sure your tyres are inflated correctly.

Increased stopping distance

Underinflated tyres have less grip on the road, which can increase your stopping distance by up to 20%. This can be a major safety hazard, especially in wet or icy conditions.

Increased risk of accidents

Overinflated tyres can also be dangerous. They have less contact with the road surface, which can reduce your grip and make it more difficult to control your vehicle. In extreme cases, overinflated tyres can even burst, which can lead to a serious accident.

Premature tyre wear

Both underinflated and overinflated tyres can wear out prematurely. This is because the tyre is not able to distribute the weight of the vehicle evenly, which can lead to uneven wear.

Problems caused by overinflated tyres

Over inflated tyres can cause a number of problems incliding:

Reduced grip

Overinflated tyres have less contact with the road surface, which reduces their grip. This can make it more difficult to control your vehicle, especially in wet or icy conditions.

Increased risk of aquaplaning

Aquaplaning is a condition that occurs when your tyres lose contact with the road surface and start to ride on a layer of water. This can be very dangerous, as it can cause you to lose control of your vehicle.

Premature tyre wear

Overinflated tyres can wear out prematurely. This is because the tyre is not able to distribute the weight of the vehicle evenly, which can lead to uneven tread wear.

Problems caused by underinflated tyres

As with overinflated tyres, underinflated tyres can cause saftey and longevity issues including:

Reduced grip

Underinflated tyres have more contact with the road surface, which can increase their grip. However, this increased grip can also lead to the tyre overheating and eventually bursting.

Increased rolling resistance

Underinflated tyres have more rolling resistance, which means that they require more energy from the engine to keep them moving. This can lead to increased fuel consumption.

Premature tyre wear

Underinflated tyres can wear out prematurely. This is because the tyre is not able to distribute the weight of the vehicle evenly, which can lead to uneven wear.

How to check your tyre pressures

The correct tyre pressure for your vehicle will be listed in your owner's manual. You can also check the tyre pressure placard or sticker, which is usually located on the driver's doorjamb. There may be multiple tyre pressure settings as pressures can be measured in Bar, pounds per square inch (PSI) and kPa.

To check your tyre pressure, you will need a tyre pressure gauge. You can purchase a tyre pressure gauge at most auto parts stores.

To check your tyre pressure, follow these steps:

1. Park your vehicle on a level surface.
2. Turn off the engine and allow the tyres to cool down (or check the tyre pressue in the morning, before driving).
3. Remove the valve caps from the tyres and attach or screw the tyre pressure gauge into the valve stem.
4. Read the tyre pressure gauge.
5. Remove the tyre pressure gauge from the tyre repeat the process to obtain a second reading.

If the tyre pressure is not within the recommended range, you will need to add or remove air from the tyre.

How often should you check your tyre pressures

You should check your tyre pressure at least once a month. You should also check your tyre pressure more often if you are driving in hot or cold weather, or if you are carrying heavy loads.

How can I find the correct tyre pressures for my vehicle?

The vehicle manufacturer will list the correct tyre pressures in your vehicle's handbook. This is the most reliable source of information on the correct tyre pressures for your vehicle. The handbook will typically list the tyre pressures for both the front and rear tyres, as well as the pressures for when the vehicle is loaded or unloaded.

You can also look for a placard or sticker on the vehicle. Some vehicles have a placard on the driver's side door sill or inside the fuel filler cap that lists the recommended tyre pressures.

You can use an online tyre pressure calculator. There are a number of online tyre pressure calculators that can help you find the correct pressures for your vehicle. These calculators typically ask for your vehicle's make, model, and year, as well as the load rating of your tyres. Ensure you enter the correct details as pressures will vary by wheel size, tyre size, date of manufacture, engine size (larger engines may be heavier) etc.

How warm weather affects tyre pressures

In warmer weather conditions, such as during the summer months, the air in your tyres tends to expand due to the heat. This can result in overinflated tyres, increasing the risk of blowouts or reduced traction. Consequently, it becomes essential to monitor your tyre pressure more frequently when driving in warm weather to maintain proper inflation levels for enhanced stability and handling.

How cold temperatures affect tyre pressures

Colder weather can cause the air inside your tyres to contract, leading to decreased tyre pressure. According to Continental, air pressure drops by 1-2 PSI or 0.07 to 0.14 bar with every 10 degrees C decrease in temperature. This reduction in tyre pressure compromises your vehicle's grip on icy or snowy roads and might increase braking distances - especially if you haven't switched to winter tyres and you are still running on summer tyres. Hence, checking tyre pressure more often during cold weather helps ensure adequate inflation for safe winter driving conditions.

How transporting heavy loads affects tyre pressure

If you frequently transport heavy loads in your vehicle, tow trailers or the vehicle contains lots of passengers and luggage, it is crucial to keep a close eye on your tyre pressure. Carrying substantial weight puts extra strain on the tyres, causing them to compress further and potentially lose air more rapidly. By inspecting your tyre pressure more frequently under these circumstances, you can identify any gradual loss of air and avoid complications like uneven wear patterns or sudden blowouts that could endanger you and others on the road.

If you inspect the recommended tyre pressures for your vehicle (these can usually be found on a sticker on the driver's door opening, or in the vehicle manual) you will probably find that two sets of recommended tyre pressures are given. One for when the vehicle is transporting the driver and a passenger, and another when the vehicle containes more passengers and luggage.

Conclusion - Check your tyre pressures regularly

Maintaining the correct tyre pressure on your vehicle is crucial for a safe and efficient driving experience, so it's important to check your tyre pressure against manufacturer guidelines.

Changes in temperature can significantly impact tyre pressure, causing underinflation or overinflation so it is essential to regularly check and adjust tyre pressures to ensure optimal performance and safety on the road. By using a tyre pressure gauge, you can easily monitor and maintain the recommended pressure levels for their vehicles. If your vehicle has an in-built tyre pressure monitoring system (sometimes known as TPS or TPMS) then tyre pressures are constantly monitored and the driver is notified of any significant changes in pressure as measured against a baseline reading.

Do not overlook the importance of correct tyre pressures and make it a habit to check your tyres regularly for safer journeys.