How to Check Tyre Pressure.
Tyres have been known to lose up to 1 psi - pounds per square inch every month. So check all tyres, including your spare, once a month (or before a long trip). It’s easy. Here’s how:
1. Purchase a trusted tyre pressure gauge.
2. Check your tyres “cold” – before you’ve driven or at least three hours after you’ve driven.
3. Insert tyre pressure gauge into the valve stem on your tyre. (If you are using a digital tyre gauge like the one pictured, the gauge should begin reading the air pressure immediately. Refer to your air pressure gauge owner’s manual for correct usage instructions. If using a "pencil" style tyre gauge, the gauge will “pop” out and show a measured number. When you hear a “pssst” sound, that’s air escaping the tyre. The escaping air shouldn’t affect pressure substantially, unless you hold down the air pressure gauge too long.)
4. Compare the measured PSI to the PSI found on the sticker inside the driver’s door of your vehicle or in owner’s manual. DO NOT compare to the PSI on your tyre’s sidewall.
5. If your PSI is above the number, let air out until it matches. If below, add air (or have a Michelin retailer help you) until it reaches the proper number.
Low tyre pressures can lead to tyre damage. See the inflation difference:
Most tyres are filled with compressed air. But some tyre retailers have started to put nitrogen into their customers’ tyres. (Nitrogen is simply dry air with the oxygen removed. Air contains nearly 79% nitrogen already.) Because nitrogen replaces oxygen, less air can escape your tyres, and your inflation pressure stays higher longer. Tyres manufactured by Michelin are designed to deliver their expected performance when inflated with air or nitrogen, as long as the user respects the pressures recommended by the vehicle manufacturer on the vehicle’s placard or by the tyre manufacturer.