Is 40 PSI Good pressure? Guides For Newbies

One of the things that you need to pay attention to when using a car is the tires’ pressure. Because it directly affects your safety level while traveling on the road.

Many drivers often wonder, “is 40 psi good pressure” and what is safe enough? 

The simple answer is yes, but not in all cases. Because each type of tire will have a different pressure rating, 40 psi may be appropriate for one tire, but it may be too high or too low for another

Let’s explore the content of the following article to understand this issue better!

Is 40 PSI pressure Good Or Too High?

40 PSI pressure Good Or Too High?
40 PSI pressure Good Or Too High?

40 psi can be a good pressure for some vehicles with specifications within this limit. However, this level may also be too high or too low for some other tires.

Specifically, the level of 40 psi can be suitable for passenger cars or sports cars. But this is too high for small cars with a recommendation below 35 psi, while 40 psi is too low for large trucks.

The recommended level for the tires of famous sports cars and passenger cars is between 32 -40 psi. The specific index will be specified depending on the type of vehicle. Note that this level is recommended when the tire is cold, so you must recheck it for proper adjustment after a long trip.

Currently, there are many different types of cars on the market, and each will use a different kind of tire. Therefore, the appropriate pressure of each of these tires will be determined by the manufacturer in advance.

Your task is to ensure the most suitable level for the vehicle to operate smoothly and safely. You need to check the tire specifications first to be able to determine if this 40 psi pressure level is suitable for your vehicle or not.

Why Does pressure Change?

Pressure Change
Pressure Change

Statistically, yours can drop by about 1-2 psi naturally due to wear and tear. Besides, there are also several other reasons why it may vary more.

Specifically, it is also affected by weather and climate. The pressure of the car in hot weather will increase, and the tires will expand. In contrast, when in cold weather conditions, the tire can shrink, then the air in the tire is reduced.

The trend in practice shows two common cases with tires: one is an under-inflated tire on the front axle, and the other is an over-inflated tire on the rear axle. 

Therefore, you need to check your tires at least once every two months. It ensures that the pressure is always under control and correct with the standard according to the vehicle’s specifications.

Besides, some unexpected events that damage the tire will also cause the pressure to change quickly. You need to pay attention to abnormal signs to repair to avoid risks when moving.

What Happens If The Pressure Is Too Low Or Too High?

In fact, traveling with a vehicle with too high or too low pressure is extremely dangerous. Not only does it cause the car to crash, but it can also even lead to an accident that endangers you.

Let’s learn about some of the situations that can happen if yours is too high or too low to understand the severity of this problem better.

Low pressure

Low Pressure
Low Pressure

First, when your pressure is too low, the sidewalls sink, leading to tread and sidewall wear. In addition, under-inflated tires also increase resistance and temperature, causing tires to wear faster; even the worst-case scenario is a tire explosion.

At the same time, when the pressure is low, the tread is prone to warping, sometimes the tire is overheated, causing increased rolling resistance and premature tire wear. 

Sometimes more severe than underinflated tires can damage the tires and be the cause of unexpected accidents.

Too high presure

Meanwhile, the high rate is also a rather dangerous problem that you need to pay attention to. Air tension directly affects the life and durability of tires. 

Therefore, inflating the tire too much leads to reduced traction and abnormal wear, especially at the communication bridge.

Inflated tires will wear out in the middle of the tread while the sides are still in pretty good condition, almost unaffected. This condition also contributes to accelerated wear in the center of the impression and reduced life.

More dangerously, when you inflate it too much, combined with high temperatures and long travel, causing the tire to heat and expand, the increased tension can cause it to explode.

How To Ensure Proper Tire tension

As can be seen, ensuring the correct wheel tension is extremely important because it directly affects your safety. Besides, moving with a suitable force helps your car save more fuel.

To ensure the proper tension level for your vehicle, you need to do a few things:

Determination of rated tension

First, you need to check the tire parameters to determine the exact tension level recommended by the manufacturer for it.

In particular, over time, this number can become blurred, and you need to remember it precisely so that you can adjust it when needed.

Keep the tension at the recommended level.

Once the correct rated tension has been determined, your task is to provide this right level for the vehicle. Be careful when inflating your tires to make sure your car is neither too inflated nor too underpowered.

Check tension

Check tension
Check tension

Yet, tension can vary due to many factors. So, you need to regularly check yours, especially before and after a long journey, to ensure the correct level.

Checking tension before setting off is considered a good habit that manufacturers recommend for all vehicles. As a result, you can save fuel during the entire journey and operate the vehicle more safely.

Besides, you should also choose a time to check the tension periodically, even if you don’t move often.

When checking the tension, you need to check all your cars (even the spare ones) because each variation is different; you cannot check representative as it is not accurate for all.

For more details, check out this video below:


It is difficult to answer the question precisely, ” is 40 psi too high” because each type will have its own recommended rating from the manufacturer.

At the same time, tension can also change during travel, so you also need to check and adjust accordingly. Do not let the tires be over-inflated or the tension is too low to ensure safety when traveling.

3 thoughts on “Is 40 PSI Good pressure? Guides For Newbies”

  1. I have a 2012 Chevrolet Impala ls but it requires 17 inch tires. When I bought car it had on 225/55r/17 97T . Last week I bought brand new tires they were supposed to be the same size and load rating but the tire place but 225/55r/17 101xw I think it’s xw or xl and it says they should be inflated with 42 psi? Is this too much air? Thank You

  2. The 97 and 101 indicate the maximum weight (load) for the tire – the 101 means the tire is capable of supporting a heavier load than the 97.
    The 42 psi marking on the tire itself is the maximum inflation psi – it is NOT the recommended psi. There is probably a label on the driver side door that shows the tire size and the ‘recommended psi’ for the tires. Different tire brands and tread designs might work better at a psi that is higher or lower than the psi shown on the door label. If your tires make a ‘ping’ noise going over road tar stripes, their psi is likely too high. If the fuel mpg has become lower, then the psi might to too low.

  3. Set the tire pressure according to your vehicles tire information placard, NOT the max pressure rating on the tire. The tire information placard is usually found on the inside of the driver’s door jamb.


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