The road trip is back.

Memorial Day weekend travel volume – the vast majority of it by automobile – is expected to reach a 10-year high in 2015, according to the AAA auto club. Some 37.2 million Americans are forecast to travel 50 or more miles from home during the holiday.

In other words, a lot of people have a lot riding on their car tires. And as we discussed in this previous post, tire pressure plays a vital role in determining fuel economy and, more important, car safety and handling.

It’s easy to check your tire pressure. Some auto service centers will do it for you for free, or you can do it yourself.

Recommended pressure for your tires: You’ll find the “operating pressure” amount (it could be different between the front and rear tires) on the driver’s side doorjamb or on a decal in your glove box. This number comes from the car manufacturer.

This should not be confused with “maximum pressure,” a number found on the side of a tire that represents the maximum amount of air you can put in without jeopardizing structural integrity. Use the operating pressure number when filling your tires.

Check pressure when tires are cold: Tire pressure is given for cold tires, so check them in the morning or after they have sat for a couple of hours. When tires are driven, they heat up and the air inside them expands, making readings several pounds higher.

Use an accurate tire pressure gauge: You can purchase a traditional “pencil” tire gauge for less than $10, while digital gauges might run several dollars more. They are available at any auto parts store. (NTB Tire & Service Centers notes that built-in gauges on air hoses or compressors at gas stations often are wrong.)

To add pressure: You can find an air compressor at a gas station; the air could be free or you might have to feed quarters into the machine. Remove the black cap from the valve stem and add air in short spurts. Check the pressure and add more air if necessary. Remember to put the cap back on when you are finished.

To let air out: If you add too much air, press down on the needle in the middle of the valve stem to release some. Re-check the pressure and, when satisfied, add the cap.

This part of your pre-trip checklist is complete.

Where are you heading this spring and summer? We’d love to hear from you in the comment section below. If you send us a postcard (546 W. Chocolate Ave., Hershey), we’ll share it on our Facebook page.

Sources: NTB Tire & Service Centers, Geobeats, Howcast.