Maintaining proper tyre inflation is relatively simple and essential to the overall tyre performance of your vehicle. A properly inflated tyre will provide longer life, quicker steering response, better fuel efficiency and a smoother ride than an improperly inflated tyre. Both under inflation and over inflation can cause headaches like premature tread wear and possible tyre failure. The best way to ensure you're getting the most out of your tyres is to check your tyre pressure on a monthly basis.
Knowing how to use a tyre pressure gauge is very simple. Here’s how to check tyre pressure and refill your tyres.
Items You Need When Checking Tyre Pressure
- Tyre pressure gauge
- Air compressor
- Pen and paper
Your tyre pressure gauge can be digital or standard. Auto parts stores typically carry both. Many workshops or accessories stores sell portable air compressors that run from your car battery or USB power port. Alternatively, you can use the air compressor found at most petrol stations.
How to Check Tyre Presure
1. Start with Cold Tyres if Possible
Vehicle manufacturers specify PSI – literally “pounds per square inch” of pressure – assuming tyres are cold. Tyres are considered cold when the vehicle has been parked for three hours or more, or if the vehicle has been driven less than 1.6 km at moderate speed. PSI is the unit your pressure gauge uses to provide readings.
2. Check the Manufacturer’s Recommended PSI
Look on the driver’s side door jamb or your owner’s manual to find the recommended cold tyre PSI for your front and rear tyres. If you cannot find it, you should consult your vehicle dealer, manufacturer, or a qualified tyre professional from the workshop.
3. Write Down the PSI for Each Tyre
If your front and rear tyres require different pressure levels, write down the correct PSI for each to avoid getting confused as you move around your vehicle checking tyre pressure.
4. Check Tyre Pressure with Your Gauge
Remove the valve cap from one of your tyres and place the pressure gauge on the valve stem. Press down hard enough so the ‘hiss’ sound disappears and your gauge provides a reading. With a standard gauge, the air pressure will push a small bar out from the bottom of the gauge. Measurement units are etched into the bar. A digital gauge will show you the reading on a screen.
Write down the reading and repeat this process for all four tyres.
5. Fill to the Recommended PSI
Use an air compressor to refill any tyres with low pressure. Many air compressors are different, so read directions carefully to be sure you’re using it correctly.
If you’re using the air compressor at a petrol station, be sure to park so that the hose will reach all four tyres. Insert change into the machine until you hear the motor running. Fill each tyre by placing the end of the hose over the valve stem and pressing on the lever.
Using a petrol station air compressor means your tyres might be “hot.” If it is necessary to adjust inflation pressure when tyres are “hot”, set their pressure to 4 psi (14 kPa) above the recommended cold inflation pressure. Recheck the inflation pressure when the tyres are cold.
After filling your tyres, use the gauge to check pressure again. At this point, it’s ok if you overfilled the tyres because you can always let some air back out. Never drive on overinflated tyres. Over inflation can result in decreased traction, premature wear, and decreased impact absorption.
6. Repeat: Check Tyre Pressure Monthly
Make the above procedure a monthly ritual. Regularly checking your tyre pressure is the best way to ensure your tyres never dip far below the optimal PSI.
Tyre Pressure Gauge Accuracy
Accuracy matters and you should keep that in mind when choosing a gauge. For just a few dollars, you can find a quality, accurate tyre pressure gauge that gives accurate readings. If you’re not sure which one to purchase, ask a professional technician which he or she recommends.
A digital tyre pressure gauge will provide accurate readings, but don’t forget that it operates on a battery. If you think having to replace the battery will prevent you from using it, it’s best to go with a standard gauge.
It’s best to use your personal tyre gauge versus those available attached to air hoses at service stations. Of all the pressure gauges out there, they’re the most likely to be weathered, and possibly inaccurate.