Proper inflation is the single most important part of tyre care. The inflation pressure on the side of the tyre is the MAXIMUM operating pressure. It is not necessarily the right inflation for your vehicle. Always use the inflation recommended by the vehicle manufacturer. You can find it in your owner's manual, posted on the edge of the driver's door, on a door post or on the inside of the glove box door. Always check inflation when tyres are COLD: when the vehicle has been driven less than a mile, or one hour or more after driving. Use a good quality tyre gauge. Note: It's natural for radial tyres to have a slight bulge in the sidewall at their proper inflation pressure. Check or adjust inflation every few weeks, before any long trip or if travelling with a heavy load. And don't forget to check the spare. Your D2D retailer can answer any questions you may have about tyre inflation.