How To Put Air in a Tire at a Gas Station

Fire up the engine and everything is working as it should. But one little yellow light stays lit on the instrument cluster: a cross-section of a tire with an exclamation mark. This is the TPMS light, and it means you have an underinflated tire. Are you prepared to handle this? Do you know how to put air in tires at a gas station?

Every driver should know how to put air in a tire at gas station air dispensers, even if you don’t pump your own gas. Here’s how to fill a tire with air at a gas station.

How much does it cost to put air in your tires at a gas station?

Expect to pay $1-$2 per session at the air pump. At one time, every gas station had an air hose snaking out from the building or the garage’s overhead door so you could fill your tires, and it was almost always free of charge. But free air isn’t really a thing anymore, so you’ll need a pocketful of change (or more likely a credit or debit card) to access the compressor. Or, save your coins and see if you can find a free air pump at a gas station in your area on freeairpump.com.

How to put air in your tires at a gas station?

Once you’re at the gas station, adding air to your tires won’t take long and it’s something anyone can do. Here’s how.

1. Park close to the air dispenser

Whether you have just one low tire or all four are in need of air, you should be prepared to check and adjust them all. Park close enough to the air compressor or dispenser at the gas station so the hose can reach all four tires.

2. Find your recommended tire pressure

Before you put any air in your tires, you should know the proper air-pressure value. You’ll find it in a few different locations:

• On the driver’s door jamb sticker. Officially known as the Tire and Loading Information Label, you’ll find it applied to either the vertical support pillar when you open the driver’s door, or on the edge of the door itself.
• In the owner’s manual. If your owner’s manual is buried deep in your glove box, still untouched from when you bought the car, crack it open to the specifications section and locate the recommended tire pressure.
• An online tire-pressure chart. Some online resources provide tire-pressure listings for most makes and models, but you’ll need to determine which kind of tire you have first.

Whatever you do, do not use the tire pressure marked on the tire sidewall. It’s the maximum rated pressure the tire can withstand and is not a safe pressure for operating your vehicle. Following this number could lead to a blowout while you’re driving.

3. Remove the valve stem caps

Once you’ve determined the correct tire pressure, remove the valve stem caps. These plastic or aluminum covers protect the valves from getting dirty or contaminated, or getting pressed. (If any of these things happen, it can cause a leak.) Simply unscrew the caps from the valve stems, but keep them safe so you can put them back on afterward.

4. Check the current tire pressure

Using a tire-pressure gauge, check the tire pressure. Press the gauge squarely against the valve stem. If you can hear air hissing out, the gauge isn’t flush against the valve stem, so move it slightly to stop the leak for an accurate pressure reading.

The gauge that’s built into the air hose shouldn’t be trusted. These get banged around, dropped, driven over and otherwise abused, so they may not read accurately. Although it’s best to use your own gauge, the built-in gauge is better than eyeballing it, if that’s all you have.

If you don’t have a tire pressure gauge, they’re readily available online as well as at department, hardware and automotive stores. Models that provide clear digital readouts can be purchased for as little as $10.

5. Enable the compressor

If you’re at a coin-operated dispenser, feed the machine with quarters and press a button to get the air flowing. If it’s free air, there might be a button you need to press, or it could just be on all the time. That’s probably the case if you follow the hose back to the dispenser or garage wall and there’s no button on it.

6. Press the air hose chuck onto the valve stem

Gas station hoses typically have an air chuck at the end, and you’ll use this just like your tire-pressure gauge. Press the air chuck flush against the valve stem. You’ll hear air coming through the hose and into your tire. If you hear air hissing past, adjust the air chuck to make it stop.

Add a little air at a time. Often, short bursts of five seconds or so are the way to go. If you overfill the tire, you’ll need to press the Schrader valve to release some of the pressure.

Some gas stations may have an automatic tire-inflator shutoff on their air hose. If that’s the case, you’ll set the desired pressure, then fill your tire until the air stops flowing. These compressors are as easy as it gets because they negate the need to check the tire pressure before or during filling.

7. Verify the adjusted pressure

Check the inflation with your tire-pressure gauge frequently. As you get within a couple of PSI (pounds per square inch) of the desired pressure, shorten the time you’re adding air to just a couple of seconds.

Once you’ve filled one tire, repeat these steps with the remaining tires. It’s a good idea to check the spare tire pressure at least once per month, but at minimum, check it when you’re topping up the other tires.

8. Put your valve stem caps on

Finish the job by putting your valve stem caps back on. Remember: they only need to be finger-tight (valve stem caps can crack easily if they’re overtightened, and aluminum caps can be next to impossible to remove if they’re too tight).

Should I over-inflate my tires in cold weather?

Have you noticed that the TPMS light comes on when it gets cold? That’s because the air inside the tire is denser as the kinetic energy decreases, and the pressure drops one to two PSI for every 10 degrees Fahrenheit the temperature drops.

It might be tempting to over-inflate your tires in anticipation of plummeting temps, but it’s not a great plan. High pressures can decrease traction by reducing the contact patch with the road. Also, tires can get damaged easier if you accidentally hit a curb or pothole.

It’s best to simply make adjustments as necessary according to the recommended pressure on the door sticker.

Does over-inflating tires save gas?

Technically, higher tire pressure can reduce road resistance, and the expected result is better fuel economy. But even the major tire manufacturers don’t recommend overfilling your tires. If there’s any benefit to fuel economy, it’s barely noticeable. And on the flip side, you’ll experience discernible differences in tire wear, and handling will be negatively affected.

How long can I drive on a low tire?

If your tire pressure is low, there can be different consequences. The tire’s rubber will heat up more than normal, the sidewall can suffer damage and your handling may feel sloppy and uneven.

If your TPMS light goes on or you notice a low tire, it isn’t recommended to drive for very long. While there are differing guidelines, you shouldn’t drive on paved roads for more than an hour or 50 miles. Better to make a pit stop as soon as possible and adjust the pressure.

Conclusion

The right tire pressure is a matter of safe driving, and every driver should know how to add air to tires at gas station compressors. It’s a simple skill that can maintain your car’s handling and prevent abnormal wear. Even if you aren’t checking tire pressures proactively every two to four weeks like some manufacturers suggest, at least deal with low pressure quickly when you encounter it.

Frequently Asked Questions