Tires are a vital part of any car. They carry the whole weight of the vehicle and act as a barrier between the car and the road. But what you might not know, is that the air inside the tire–more specifically the amount of air– is just as important.
An overinflated tire could burst while driving, and an underinflated tire could wear more quickly. Maintaining proper pressure will help ensure safety for you as a driver, as well as for your wallet. Something as simple as tire pressure could be costing you money without you even knowing!
The good news is that it doesn’t take much time at all to monitor your tire pressure. Unlike oil changes and detailing – which can take hours – checking your tire pressure only takes about five minutes! But since it’s so easy to do, now there isn’t any excuse for you to put off doing it.
If you feel lost and overwhelmed when it comes to the technical side of cars – especially something as specific as tire pressure – there are lots of resources to help.
What Should My Tire Pressure Be?
You have probably looked at your tires and asked yourself, “what should my tire pressure be?” and didn’t know where to begin. Well, I will tell you everything you need to know about maintaining a healthy tire pressure for your car and extending tire life and reducing the chance of tire failure.
It is recommended by the National Highway Traffic Safety Administration (NHTSA) that you check tire pressure at least once a month. And that by doing so, you can extend the life of your tires by 4,700 miles. You could drive over halfway around the world with those extra miles.
One thing to know before we get started is that recommended tire pressure varies depending on your type of vehicle, and even vehicle to vehicle within that category, so your first port of call should be your car’s tire pressure sticker, usually located in either the fuel filler tube door, or the driver’s side door.
Alternatively, you could find it in your vehicle manufacturer’s information pack for your car, where it will usually be somewhere under the “tires” subheading.
That being said, as a general rule, recommended psi for each type of car is as follows:
- Small Cars: Average tire inflation of about: 25-32 PSI
- Medium Sized Cars: Average tire inflation of about: 30-35 PSI
- SUVs: Average tire inflation 32-40 PSI
- Pick-Up Trucks: Average tire inflation of about: 38-40 PSI
It should also be mentioned, however, that for some cars (especially small cars) proper tire pressure also changes depending on how much weight you have in the car, so if you’re planning to fill your car with lots of weight, or go on a long car journey with lots of people, that you double-check your manufacturer’s guide for increased loads.
How Does Tire Pressure Affect My Car?
If you’re a fan of auto racing, then you have probably heard of the importance of tire pressure. I remember playing the NASCAR video game on my PlayStation as a kid, and toggling the different PSIs my car’s tires would have. It is shocking how big of a difference a change one way or the other can make.
This doesn’t just apply to racecars, this applies to personal vehicles too! One small change in either direction can greatly impact the ride, feel, and comfort of your drive. More importantly, it can greatly affect the safety of your car while on the road at high and low speeds.
Tire pressure will also affect your fuel economy too. Both overinflation and underinflation especially will reduce tire performance, thus increasing your gas mileage (which ultimately means you’ll be at the gas station more often, spending more of your money on increasingly expensive fuel).
How Do I Know My Car’s PSI Rating?
On every car, a Tire and Loading Information Label tells you what the manufacturer of your vehicle recommends your tire pressure should be. On some vehicles, it is on the edge of the driver’s side door, or it could be in the glove box, and of course, it’s in the driver’s manual. On my Ford Explorer, it is actually on the visor!
Tire pressure is measured in Pounds per Square Inch, also known as PSI. For most cars, it is somewhere around 30 PSI. This number might be different between your front tires and your rear tires. On my Ford Explorer, both sets of tires need 32 PSI.
The NHTSA also mandates that every tire have the maximum possible pressure molded into the sidewall. This tells you what the maximum pressure of your tire can be without it spontaneously combusting. Manufacturers will certainly recommend a lower pressure, as to ensure the safety of the car passengers and avoid a blowout. Especially when the vehicle is loaded to its projected gross weight (basically what your car would normally weigh with you and your belongings in it).
Is My Tire Pressure The Same All Year?
Your tire pressure changes with temperature. Typically, for every 10 degrees Fahrenheit (or 6 degrees Celsius) in change, your tire pressure will either rise or fall by 1 PSI. Warm tires gain pressure, while cool tires lose pressure. It is standard practice to check your tire pressure when your tires are cool, or when you haven’t driven for at least three hours.
Now, you might ask “do I need to adjust my tire pressure every time the weather changes?” and that is fair to ask. The answer is no, you don’t need to adjust it every day. But it is recommended to add 3 PSIs above your tire pressure when driving in cold weather.
Since your pressure drops in cooler temperatures, you will need more air to support this pressure drop and ensure a healthy tire. In the summertime, you will always fill your tires to the usual PSI number given by the manufacturer, as there is no drop in pressure.
There is also no need to take any air out in the summer, as most manufacturers will test their tires in mild climate conditions. So in the summer, your PSI number will work perfectly with your vehicle.
Why Do I Need A Tire Pressure Gauge?
You can go to any car shop and ask them to check your pressure for you. But since it’s something you will be doing monthly, it might be worth the investment to buy your own tire pressure gauge. They can cost anywhere from $5 to $20, depending on the quality and amount of features it has—such as if it’s digital or uses a piston.
I prefer to use the TireTrek Premium gauge, as I find it to be the most accurate. A gauge has a needle or bead on one end that’s connected to a tube. The needle lets air from your tire into the tube and pushes a piston up. This piston has markings on it that will tell you what your pressure is. Or if your gauge is digital, then a display will tell you the exact number.
You also might want to watch a YouTube video showing how to do it. I remember when I first tried, I didn’t get the needle into my tire properly and I thought my tire pressure was 5 PSI. I’m pretty sure flat tires have more pressure than that!
You also need to remember to check the tire pressure on your spare as well. You don’t see it regularly enough to tell when it’s going flat, and you certainly will want it to have enough air in it when the time comes to use it!
Tire Pressure Monitoring System (TPMS)
If you have a newer vehicle that comes with a Tire Pressure Monitoring System– or an automatic alert for when your tires are flat—you still should manually check. It works by sensors that are stored within your tires, and measure things like wheel speed. These sensors collect information and send it to your car’s computer to alert you when you have low tire pressure.
If your car has TPMS, it will appear as one of the two symbols the Federal Standard will allow. It could appear as a light showing the cross-section of a tire with an exclamation mark inside. The other option is a view from the top of a car with all four tires exposed.
One of these two symbols will appear as a light on your dashboard, and that means it is time to check out your tires. If your symbols blink on briefly and then turn back off, that means that the pressure was poor but then came back. This could happen on a cold morning before your tires heat up as we talked about earlier.
These systems will only tell you when your tire’s PSI is much more deflated than you would ever want to be, and can only detect a difference in the tire when the pressure is so low that it affects your wheel rotation.
Look, I don’t know about you, but I would want to know about my tire being low before the extra damage to my tread has already happened. Tires cost a hundred bucks a pop, and while the monitoring system is accurate enough, I’d like to be sure and still keep my eye on the tires.
On my mom’s 2017 Honda CRV, her “check-tire” light went on, and when we looked at the tire, it was much more worn down than her other tires. Even at a slightly lower PSI, her tire was wearing faster and she didn’t get an alert because it wasn’t at a dangerous level yet. She still had to replace the tire, and she was not happy about it.
How Do I Put Air In My Car?
If you find that your tire is low, filling it up with air is as easy as can be. Most gas stations will have air compressors for you to use. To use them, you first locate the valve stem on your tire. This should stick out of your wheel about one to two inches. This is located between the spokes on your wheel.
Next, you take off the valve cap and expose the intake tube. Which looks like a circle with a needle sticking out of it. The needle is a pin, and when you apply pressure it will open up the valve. All you have to do is take the end of the air pump and securely connect the end to your valve intake. The pump will press the pin and force air into your tire.
After you have filled up your tire, make sure to double-check using the gauge to see if you put in enough or if it needs more!
Why Is Tire Pressure Important?
Having properly inflated tires ensures the tread wears evenly and maximizes the life of your tires. You might feel that lower pressure gives your car a smoother ride because it absorbs more bumps and hazards, but there is a cost. When your tire is underinflated, there is more rubber meeting the road, and that extra friction will cause tread wear.
This added friction also causes your engine to have to work harder. And when your engine is working harder, it is burning more fuel. If you notice your car’s fuel efficiency is worse than normal, check your tires and you might find the problem!
Many states have tire pressure regulations for this exact reason. In California, you must provide documentation at each car servicing showing that your air pressure was checked and had appropriate pressure. This is to ensure that each personal vehicle is burning less fuel and contributing less pollution into the air.
This is extra important to me because my Explorer gets terrible fuel mileage anyways. So you already know I’m checking my tires constantly because it is expensive to go from 15 mpg to 12 mpg. On a 16-gallon tank, that is 48 miles that I’m losing just because of tire pressure.
Having over-inflated tires is also an issue. When your tires have too much air it forces your tires to bounce more on the road. This will decrease your traction and stopping distance in your vehicle, especially in the rain when it is most important.
You will also feel every bump and rock on the road. When your tires have no give, then every little inconsistency is felt by you in the cabin, greatly decreasing your ride comfort. This added pressure on your tires also makes them more susceptible to damage from potholes and other road hazards.
How Do I Remove Air From My Tire?
If your enthusiasm for filling your tires up causes you to go overboard — and now your tire feels more like a rock than a tire — don’t worry, because taking the air out of your tire is even easier than putting it in.
To remove air from your tire, you use a very similar process to putting it in there in the first place. Remove the valve cap and take a narrow metal screwdriver and press the pin to release air. A pair of needle nose pliers can work too.
Don’t be afraid to practice a few times, because at first, it can be difficult. Trust me, from my own experience it might take lots of practice. But once you figure it all out, make sure to use the tire pressure gauge again to see if you let out the right amount.
What About My Trailer?
Now we’re talking. If you are driving a heavy commercial vehicle or towing your horses around in a trailer, then you are a cooler guy than I am. But also, your rules are the same for your tires – just…. bigger.
Standard PSI for any vehicle weighing 34,000 pounds per tandem axel (trucking folks know what I’m talking about) is going to be 75-80 PSI. And this is standard all around. As I said, every manufacturer has instructions, so if you’ve got a little bit less junk in your trunk then we might be working with a lower PSI.
But for the big boys, you will be perfect with 80 PSI in your tires. And with these larger load vehicles, it is even more important to check up on the tire pressure to ensure you don’t have a blowout on the interstate.
Imagine going downhill in a vehicle that weighs the same as 10 elephants and you lose one of your tires. Luckily, trucking companies have very high standards, and you don’t need to hear from me about the importance of proper tire maintenance. But it’s still an important subject to talk about.
In summary, the most important thing to remember is that every question you have about your car’s tire pressure comes with an easy answer given to you by the manufacturer! That is a relief to me because I don’t have to do any math or go to a car shop to figure it out. All the info we need is easily accessible.
Don’t forget to check out our website if you have any other questions about your tires.
Checking your tire pressure monthly will also alert you to early issues with your tire that can be fixed before the tire is ruined. For example, if your pressure consistently drops 5-8 PSI each month, then you might have a small leak that can be patched. But if you wait too long, then the tire could blow out and you would lose it completely.
Always remember to keep your tire gauge in your glove box or somewhere in your car where it is easy to find. They are pretty inexpensive and easy to replace, but it would be better if you didn’t have to every month.
Tires are the one thing separating you from the road, so take good care of them. Better to spend 5 minutes a month maintaining them than to spend hours in the mechanic shop getting them replaced!
Before you go, please don’t forget to check out our tire reviews. Happy tire buying!