How to Check Tire Pressure

You could be driving around and not know that your tire pressure is low or too high—which is also dangerous. The tire looks full. The car is moving. Unfortunately, a tire doesn’t have to look flat or bloated to have bad tire pressure. 

Knowing how to check tire pressure based on manufacturer specifications and driving conditions can help save you money on tires and gas. It will also prevent nasty blowouts, flats, needless accidents and damage to your alignment. 

Let’s check out how every driver, regardless of mechanical skills, can perform this simple maintenance measure.

Why Tire Pressure is Important 

Tire pressure is important because damaging your car is expensive—and unsafe. Optimal tire pressure is an easy and important part of your vehicle’s health. Here’s why:

1. Good tire pressure helps prevent flats and blowouts.

2. Equalized tires are better on your alignment and help keep tread wear even.

3. The wrong tire pressure increases wear and tear on your tires.

4. Over-inflated tires mean less rubber on the road, decreasing handling and making you more vulnerable to accidents. 

5. Wet weather driving and defensive drivingDefensive Driving—when breaking and handling are critical— are more difficult with worn tread, bad alignment or over-inflated tires. 

How to Check Tire Pressure

Behind-the-wheel drivers trainingBehind The Wheel Drivers Training will teach you how to operate a vehicle, but maintenance is an entirely separate issue. Checking tire pressure is one of the easiest maintenance measures for vehicle owners to do on their own. Many vehicles are built with electronic tire pressure gauges, but it’s best not to rely on them. Knowing how to check tire pressure the manual way is a skill worth learning. 

Where to Check Tire Pressure

It’s best to check your tire pressure at home. Driving on the tires can heat them up, making you misread tire pressure. If not, choose a place as close to your home or work as possible. For the most accuracy, you can get a portable air compressor for home use. 

How Tire Pressure Gauges Work

A tire pressure gauge will read the PSI of your tire by attaching to the nozzle. The tire pressure, or PSI, is the number on the bottom of the gauge, towards the hose. On the air compressor hose used to inflate tires, the gauge will pop up once it’s in place. 

You can also buy a traditional or digital tire pressure gauge. (The simple ones work fine.) Tire pressure gauges are available at almost any car store, gas station or big store with a car section. 

Simple Steps for Checking Tire Pressure 

1. Identify the recommended PSI in your driver manual or driver door jamb.

2. Check that the recommended PSI is not higher than the PSI on the tire sidewall.

3. Remove the nozzle cap from the tire. 

4. Using a tire gauge, check each tire for its PSI while the engine is cold. 

5. Using an air compressor, fill each tire to the recommended PSI—or special PSI if applicable. 

6. Replace the nozzle cap.

That’s it! All it takes is about 5-10 minutes from start to finish. 

Tire Pressure FAQ - Everything You Need to Know About Checking Tire Pressure

How do I know what my tire pressure should be? 

You can find the recommended tire pressure in your driver’s manual and on the driver’s door frame. 

The recommended air pressure is measured in pounds per square inch, or PSI. While the recommended PSI is accurate for normal driving conditions, fully read your manual to find exceptions for extreme weather and other special circumstances. 

Once you know the recommended PSI (or special PSI), you can check each tire on an air gauge. Check each tire when the car is cold and check it several times for the most accurate reading. 

Tires have their own pressure limits: 

Tires are not one size fits all when it comes to air pressure. Ideal PSI for your car can differ due to a tire’s PSI capacity. Check your car’s recommended PSI before buying tires. It’s best to make sure you have the right tire for your car’s recommended PSI under normal driving conditions.

The PSI number on the sidewall of your tire is not the recommended tire pressure for your car. It is the highest PSI that specific tire can safely handle. Your car’s recommended tire pressure may have a different, even higher PSI than the tire can handle. If this is the case, stick with the maximum PSI listed on the tire.

Variations in recommended tire pressure: 

There are various conditions that change the recommended tire pressure. Weather conditions, elevation, heavy loads and other circumstances change the recommended PSI. The most standard variations are cold PSI and hot PSI. 

Cold weather car care includes adjusting air pressure to the cold PSI. In extremes, your car may need snow tires, which can add strength and traction. But even if you aren’t going through snowy mountain roads, cold weather changes the pressure in your tires. 

Hot weather also changes tire pressure. As the heat expands air, tire pressure in hot weatherHow To Drive In Extreme Heat Driving Resources increases by about 1 PSI for every 10 degrees. If you live in a very hot climate or summers in your region are air-condition required, be sure to determine the hot PSI for your vehicle and adjust your tire pressure accordingly. 

Tire pressure varies under the following conditions, depending on the vehicle:

• Normal recommended tire pressure

• Hot tire pressure

• Cold tire pressure

• Number of passengers

• Towing or hauling

• Tire strength, which may be different than your car’s recommended PSI

How often should I check tire pressure? 

A monthly tire check is the surest way to maintain the best fuel economy and safest drive. However, check immediately before and after any special conditions like a heatwave, cold spell or long trip. 

Do NOT forget to check your spare for proper tire pressure as well. This is particularly important when planning road trips. Put it on your road trip checklist. 

Check your tire pressure if any of the following conditions occur: 

• The car pulls to the left or right when driving straight (this could also be your alignment).

• You have to give it more gas to go than usual.

• Loose handling, sliding, skidding or anything that requires extra strain on your braking.

• Tread is more worn or smoother in the center of the tire. That can mean over-inflation. 

Checking Your Tires for Wear and Tear

Since you’re looking at your tires already, check the tread along with the tire pressure. Check for other dangerous conditions like cracks in the sidewall, nails or other intruding objects and tears in the rubber. If you can, examine the tread to make sure there are no bald spots or heavy wear. 

Measuring tire treadMaintenance Tires Driving Resources is an essential part of safe driving and it only takes a minute. Tires don’t always wear evenly, so check all four. You can use the penny test to check tread wearTrending Handling Tire Blowout Plus Penny Tread Tests And Regular Rotation Defensive Driving to figure out if you need to replace your tires. If you think the tires may be over-inflated, use the penny on the middle and side of the tire.

Why does tire pressure change my fuel economy? 

Under-inflated tires resist rolling. It’s like trying to roll a slightly rounded rectangle. That means you have to use more energy to maintain the same speeds. And that lowers your fuel economy. 

Do not over-inflate your tires thinking you’ll save money at the pump. It won’t reduce fuel consumption, and it can be dangerous. 

Have a question about vehicle maintenance or getting a drivers licenseDrivers Ed so you can start taking care of a car? Ask the experts at iDriveSafely or check out the blog for more helpful information. 

*This article was updated on 5/28/2020