What is the Best PSI for Car Tires
Do you know what air pressure your car tires should be inflated to? It's important because it affects safety, fuel economy, performance, and tire wear. While many modern cars come equipped with tire pressure monitoring systems, it's best that you learn how to check your tires monthly.
There are three main types of psi ratings: PSI, BAR, and TPSi. Each type has its pros and cons, but we'll focus on PSI here.
If you've never heard of PSI before, it stands for pounds per square inch. This number tells you how much pressure is inside each tire. A higher PSI rating means more air in the tire, which makes the tire harder and provide a firmer ride. But a lower PSI rating means less air in the tire, making a softer and cushier ride.
The ideal PSI rating depends on the vehicle and the conditions. For example, if you're driving on dry pavement with low speeds, a high PSI rating will help you get faster acceleration. On wet roads, a lower PSI rating will make your tires slip less, giving you better traction.
But every car manufacturer has an easy way to determine the ideal PSI for your car based on your load.
In this article, we will cover how to find the correct PSI rating for your vehicle. And what does it even mean anyway? Here's everything you need to know about PSI.
What is the Best Tire Pressure for My Tires?
To find out what the correct tire pressure is, you can check the owner's manual. But you can also look inside the driver's door pillar for a sticker. The sticker will indicate the ideal PSI for your front and rear tires. In my example, BMW indicates that the front tires can be 34 PSI and the rear is 42 PSI.
If you do not see a sticker on your car, then you can select a range from 33 - 36 PSI as a good starting point.
Tire pressure should be checked every month and this is especially true when seasons change.
Checking tire pressure once a week isn't necessary, but it's a good habit to check the essentials like tire pressure, oil and coolant.
Is It Bad to Drive With Under-Inflated Tires?
Driving on under inflated or overinflated tires is dangerous. Driving on under inflated tires will damage the sidewall and may damage the tire tire bead. If the sidewalls are compromised then you will have to replace the tires. Read more about how often to change your tires.
In addition, under inflated tires will lower your MPG and fuel efficiency. Plus the handling might be unstable because the sidewall is flexing too much under cornering.
Can Over-Inflated Tires Be Better Fuel Efficiency?
Driving with very overinflated tires is dangerous because it can lead to blowouts. I don't recommend running pressures higher than the maximum pressure of a vehicle manufacturer's rating. Higher PSI and maximum pressure can lead to higher chance of pothole damage as the tire cannot react to the impact. Your ride comfort will decrease and suffer.
While you will feel the road more, the rate of pressure is the law of diminishing return. However, slightly overinflated tires can help increase fuel economy as reported by some hypermiling fans.
How to Check Tire Pressure
Tire gauges are relatively cheap and quickly let you know the air pressure in all 4 tires. They are easy to use and don't require much maintenance. There are analog versions and styles that have a digital gauge. Either way they are affordable. You'll want to make sure you're checking the correct pressure for your vehicle. If you do it wrong, you could end up damaging your car.
First, it's best to check the tires when they are cold. As you drive, the friction and distance will warm up the tires and increase the tire pressure by 3 PSI - 5 PSI. In hot weather like the summer, it can be higher than 5 PSI but it will stabilize as you continue to drive.
How to Check for Proper Tire Inflation
- Open your driver's door and check the sticker. Your front tires might have a different setting when compared to the rear.
- Unscrew the plastic cap from the tire valve stem and keep it in a safe place.
- Place the tire pressure gauge on the valve stem. Air will rush out. Try to avoid losing too much air as you want to get an accurate reading of the air pressure.
- Hold the tire gauge and look at the reading.
- Most likely you will need to add a little air.
- Go to your nearest fueling station to look for an air machine. Otherwise, you can look at investing in a portable air pump.
- When checking the tire pressure, remember to check the spare wheel as well. A punctured tire could mean that the spare isn't inflated either.
Check the tire pressure before every trip. This includes filling up gas, getting groceries, etc. It's important to know how many miles you've driven since you last checked the pressure.
If you notice anything unusual about your tires, such as uneven wear, bulging sidewalls, or cracking tread, take note of what you see and bring it to your local mechanic.
Make sure all tires are inflated correctly. Before starting your car, look under the hood and check the tires. Look for signs of low inflation including flat spots, bulging side walls or cracked tread
How Tire Pressure Affects Grip and Tire Performance
When you overinflate your tires with maximum pressure, you are creating a smaller contact patch, leading to less traction and therefore making it easier for water to penetrate the tread area and chances of hydroplaning.
Underflating your tires creates a larger contact patch and increases the amount of friction, reducing the likelihood of hydroplaning. However, overinflated tires lose some of their ability to dissipate heat and become more susceptible to damage.
Signs of Under-Inflated Tires
When tires are underinflated they wear out faster than usual. You might not notice too much, but an underinflated tire might drive mushy or wobbly on the road. This is due to the sidewall not having enough support by the tire pressure.
In fact, according to NHTSA statistics, driving on underinflated tires increases your chance of being involved in an auto accident by 300%.
Under inflated tires can also lead to tire failure as well. As mentioned previously, the sidewall can be damaged if the weight of the rim is on the rubber. Another hazard is to lose the tire bead under aggressive driving or cornering.
Commonly, underinflated tires will decrease your fuel economy. Visually, it's hard to tell if a tire is low in tire pressure so it's good to check your tire pressure monthly.
Final Word on Tire Pressure
In conclusion, the best air pressure for your car tire depends on where you live and what type of driving conditions you typically face. In general, however, a good rule of thumb is anywhere between 33 PSI and 38 PSI is a good range.
Remember, improperly inflated tires can lead to premature wear and tear, which means that you'll end up spending more money on repairs than you would have otherwise. So, whether you're planning on hitting the road or heading straight to the garage, make sure that you check your tire pressure for the best performance. Check out our article about how to read the tire numbers on your car.