By Shawn Furman
Last Updated August 30, 2021
Most modern passenger cars come with manufacturers recommended tire pressure of about 35 pounds per square inch or PSI.
Some vehicles require slightly lower or slightly higher pressures. Regardless of what your vehicle requires, most manufacturers fit a sticker on the driver-side doorjamb showing the appropriate PSI for your vehicle. If there is no sticker, your owner’s manual should have inflation amounts listed.
The recommended inflation amount is always based on a cold tire temperature. It is recommended that tires always are kept inflated to the closest value set by the vehicle manufacturer, but most vehicles equipped with a tire pressure monitoring system will alert the driver to values about ten percent less than the specified PSI.
Technically, any PSI below the recommended amount is too low, but a deviation of more than ten percent is considered by most to be too low – for a vehicle requiring tire inflation to 35 PSI, a pressure which reads about 31 or 32 PSI is considered underinflated. Some manufacturers can allow up to twenty-five percent air loss before the TPMS light is illuminated. A tire that shows 20 PSI or lower is usually considered to be flat.
Besides a nail or other object putting a hole in the tire itself, the two most common issues that affect tire pressure are a slow leak and air temperature.
A slow leak is similar to a hole or a tire puncture, but rather than having a puncture which leads to a completely flat tire in a short amount of time, a slow leak is usually much more drawn out.
It can be the result of an improper seal between the wheel and tire upon application of new tires, damaged wheels, cracking tires, damaged air valve, or a previous puncture that has been repaired poorly or that has come undone. Unlike a common tire puncture, the chances of having to replace the tire because of the amount of damage are much more unlikely.
The more common factor that affects tire pressure is the air temperature.
As air warms, it expands. As it cools, it contracts. This is why so many people start their vehicles on a cold morning and find the TPMS system showing low air pressure, even if it has not come on in weeks or months.
This is also why manufacturers and mechanics recommend inflating your tires when they are cool – that is when the vehicle has not been in use recently and has been sitting, not necessarily when the tires are cooled to a certain temperature.
The low tire pressure warning light in the instrument cluster is the most obvious way to know when one or more of your tires is too low. TPMS systems were mandated on all vehicles sold starting in 2008, so it is becoming harder to find one without this equipped.
Not all pre-2008 vehicles had this though, and there are still plenty of vehicles on the road that may not be equipped with TPMS. You will know if your vehicle has a tire pressure system by the flat tire icon that lights up when you turn on the ignition.
If you are still unsure, your owner’s manual will have further information. Regardless of whether or not your vehicle has a TPMS system or not, it is good practice to check your tire pressure twice a month as even a small amount of air loss can have long-term impacts if not rectified.
Tires are designed to provide the best possible fuel economy when properly inflated by combining grip with the surface area. Similarly to kicking an inflated ball versus kicking one that is not inflated, tires can bog down a vehicle, causing the engine to work harder to make it move.
A small amount of deflation may not be recognizable when you are driving, but when a vehicle is traveling at high speeds, it can make a large difference.
Some sources even estimate that a loss of up to three miles per gallon could be caused by the under-inflation of tires. This will most likely happen if there is more than one tire that is underinflated at a time.
Premature tire wear is another sign that your tire pressure is too low.
Rather than having a uniform tread across the tire, an underinflated tire will wear down on each side with the tread remaining thicker in the middle.
The opposite will occur with an over-inflated tire where the middle of the tire will show premature balding. This is not always an obvious sign of inadequate tire pressure, especially if the tires were just installed. Even though this process might take over a year, it usually becomes obvious which tires have suffered the most from under inflation.
Another sign that your tire pressure might be too low is an increase in stopping distance from what is normal. A keen driver will notice this more than the average commuter as this is also not always the most obvious sign of under inflation, but studies show that stopping distances can be severely inhibited by under-inflated tires. In cases like these, it will become more obvious. The problem becomes even worse during rainy and snowy conditions.
Steering and driving feel are the most obvious ways to tell if your tire pressure is too low, especially if you have had your vehicle for a while and know what it is like to drive.
Vehicles were built to handle a specific way under ideal conditions, and low tire pressure affects these conditions negatively. Sloppy handling, pulling to one side, difficulty keeping the vehicle driving in a straight line, not being able to steer precisely, and a generally unsettled ride can all point to low tire pressure.
All of this becomes compounded in adverse weather conditions, and in some severe instances, it can cause the vehicle to lose all traction.
Driving with low tire pressure is a fairly common problem, but it is also one of the most dangerous. Two very serious consequences can occur as a result.
It has already been mentioned that a vehicle’s handling and steering becomes less effective when low tire pressure comes into play and that poor weather conditions can expose these issues even more.
Sudden loss of control can happen at any time when a vehicle’s tires are under-inflated, and when driving at speed, any loss of traction can cause an accident, even if no signs of irregular handling had been present before.
This consequence of low tire pressure accounts for several thousand accidents per year.
Tire blowouts are the most dangerous consequence of low tire pressure, and they are caused by a weakened tire structure or an excessive amount of wear. Low tire pressure, coupled with the weight of the vehicle and heavy tire loads can cause one or more parts of the tire to suddenly fail. Most blowouts usually happen without warning, the main reason they can be deadly.
If a blowout occurs on your vehicle, it is important to stay calm. Usually, you will hear a loud bang, quickly followed by a sudden jerk to one side or the other.
To avoid an accident, grab the steering wheel tightly, briefly press the accelerator to resettle and realign the vehicle, then let it gradually slow down by itself as you pull to the side of the road. Once the vehicle slows to about 20-30 miles per hour, you may slowly press the brake to fully bring the vehicle to a stop.
Tire pressure becomes too low when it drops below the manufacturers recommended inflated value, often found on a sticker on the driver’s side doorjamb of a vehicle.
The pressure is measured in pounds per square inch, and tire pressure monitoring systems usually alert the driver to pressures that drop about ten to twenty-five percent below recommended value – usually around 35 PSI.
Checking tire pressure about two times per month can ensure that premature tire wear, increased braking distances, inadequate steering, and accidents are avoided because of low tire pressures.
The National Highway Traffic Safety Administration found that there are nearly 11,000 tire-related motor vehicle crashes each year—many of these accidents are a result of tire underinflation.
Beyond safety, underinflated tires can cost small businesses a lot of money in fuel, maintenance, repairs, and more.
Adequate tire pressure is essential in keeping your drivers and vehicles safe, and your company running smoothly.
Here’s all the information you need to know about the effects of low tire pressure:
If you drive a car with low tire pressure, you can expect lowered fuel efficiency, compromised tire performance and lifespan, and elevated risk to the driver’s safety and the safety of others on the road.
When a tire’s air pressure is low, the handling is compromised and there is an increased risk of tire failure.
Let’s discuss these effects of low tire pressure in more detail below:
Low tire pressure leads to low fuel efficiency. When tire pressure is low, there is more of the tire’s surface on the road, causing more drag, which requires more power from the car to mobilize itself.
There is a 2% loss in gas mileage for every 5 pounds per square inch (psi) a tire is underinflated. Your fleet vehicles’ fuel economy relies heavily on proper air pressure in the tires.
While a misconception may be that low tire pressure decreases acceleration, low tire pressure can actually increase acceleration; however, low pressure can lead to faster degradation of the tires, among other risks mentioned in this article.
When tires have low air pressure, more surface touches the road and leads to premature and uneven wear and tear. The extra contact with the road causes heavy wear on both the inner and outer shoulders of the tire, which leads to worn-down tread and poor tire traction. Premature and uneven tire wear means more frequent tire maintenance, repairs, and replacements.
Low tire pressure puts more weight and force on your vehicle’s tires which causes the tread to shorten in less time than usual. Short tire tread can lead to flat tires which are a huge safety concern while driving on the road. When tires are kept at their optimal air pressure, the tread will stay intact for longer and lower the risk of a risky or inconvenient flat tire.
When a tire is underinflated, its sidewalls flex more than they are designed to while handling—specifically when braking, cornering, and steering.
Low tire pressure increases braking distance length and slows down response time to steering.
This can be incredibly dangerous in an emergency situation when every fraction of a second counts and a vehicle’s response could mean life or death. For example, if your vehicle has underinflated tires, the risk of hydroplaning increases significantly at lower speeds than it would be with properly inflated tires.
A tire blowout is the most dangerous risk associated with low tire pressure. With more of the tire’s surface touching the road and warming up the rubber, this can cause the tire to overheat and blowout.
Tire blowouts happen suddenly and cause the driver to lose control of the vehicle. In many cases, leading to SUV rollovers or car accidents. Blowouts are more likely to occur at higher speeds which makes them extremely dangerous and life-threatening.
Avoiding low tire pressure takes consistent monitoring.
You should check your fleet’s tire pressure once a month, as the temperature outside will impact the air pressure within the tires and cause it to change as the air temperature changes.
Your team should use a combination of visual checks, manual checks, and monitoring technology to avoid low tire pressure.
Have your drivers or maintenance team perform a visual check on the tires every day. If they notice an underinflated tire, they should examine the tire further before getting in and driving the vehicle. Further examination is explained below.
The best way to get a proper read on a vehicle’s tire pressure is by using a tire pressure gauge. These can be bought at your local hardware store or auto parts store. These tools will get you a precise and direct read of each tire’s psi.
Vehicles made in 2008 or after should be equipped with a Tire Pressure Monitoring System (TPMS).
If they detect your tire pressure is low, a light will notify you on your dashboard to check the tire pressure. A vehicle’s TPMS has a lifespan of about five to 10 years so this should be kept in mind during maintenance.
Many fleet tracking systems include vehicle maintenance features that help fleet managers know if and when their vehicles need to be checked for deflated tires. (This is just one of the many major advantages of vehicle tracking for small businesses.)
Pro tip: Consider adding these tips for avoiding low tire pressure into your company’s fleet vehicle maintenance checklist to ensure they get done.
Before adding more air to your fleet’s tires, you’ll want to make sure you know exactly how much psi is required in each set of tires. This information can be found in the owner’s manual, on the sticker on the inside of the driver side door, or on the actual tire itself.
Most passenger car tires require 32 psi to 35 psi, so, yes, 28 psi is too low for tire pressure. Make sure each tire is filled with the proper pressure and that the stem caps are put back on securely afterwards.
It is not advised to drive on a tire with low pressure. If you must do so, it should only be done to get out of harm’s way and tires should be inflated as soon as possible once the low tire pressure signal has turned on.
Injury or death as a result of low tire pressure accidents could significantly impact a small business. Keeping your eye on something as simple as tire pressure can have a positive and long-lasting impact on your fleet’s health and your drivers’ safety.
Force by Mojio offers fleet vehicle health and maintenance software for small business fleets that can help with tire pressure and more to help keep your vehicles and your drivers safe.
Try it free for 30 days and get real-time information on vehicle health, driver behavior, vehicle tracking, and more.
What should be the pressure in the tires of the car? Does it need to be adjusted and what will happen if the pressure is changed in one direction or another?
Two friends conversation:
- Hello, I lowered the wheel!
— Not at all?
- No, only from below ...
Humor from the Web
Let's start with platitudes. The pressure must be as specified by the vehicle manufacturer. And since the average modern driver usually does not have such information, especially for him, a "cheat sheet" with the necessary numbers is hung on the middle pillar on the driver's side or on the gas tank hatch cover.
A relatively rare solution: the "reminder" is located on the gas tank cap.
A relatively rare solution: the "reminder" is located on the gas tank cap.
An important point: pressure should be measured only on cold tires. By the way, especially for pedants: cold tires are those on which the car has been without movement for at least 5 hours.
This "cheat sheet" nestled on the driver's door. An example of how tire pressure recommendations change depending on tire size.
This "cheat sheet" nestled on the driver's door. An example of how tire pressure recommendations change depending on tire size.
Since car manufacturers allow the use of tires of different sizes, the pressure may also be different. In addition, the pressure in the front and rear tires has the right to both differ and be the same.
And here there is no difference in recommendations: what is in front, what is behind is the same.
And here there is no difference in recommendations: what is in front, what is behind is the same.
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Reduced pressure leads to an increase in tire deformation, more heating during wheel rolling, accelerated wear of the outer tread tracks. Perhaps even a violation of the integrity of the frame. As a result, fuel consumption increases. If you hit a hole in the road, the likelihood of damage to both the disk and the tire is higher.
Increased pressure is an overstrain of the cords, increased wear of the middle part of the tread. In addition, when driving on a bad road, the shocks that are transmitted to the suspension and body will become more noticeable for riders. When hit in a pit, the likelihood of a tire burst increases.
Uneven pressure on all four wheels is the worst thing! At the same time, the car, while driving, inevitably leads the wheels with lower pressure to the side - in fact, sideways movement begins.
Tube tires of the past required a weekly check, especially before the advent of butyl tubes. Then the pressure began to be checked less often, and nowadays, as a rule, they are limited to visual inspection.
Tube tires of the past required a weekly inspection, especially before the advent of butyl rubber tubes. Then the pressure began to be checked less often, and nowadays, as a rule, they are limited to visual inspection.
In a good way, you need to check the tire pressure at least once a month. And before a long journey - just a must.
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The air pressure in an enclosed space changes by approximately 0. 1 bar for every 10 degrees of temperature change. This allows, having installed summer wheels in April, not to worry about the pressure in them until the end of August, when the air temperature begins to drop. Having pumped up the wheels at the end of summer, you can already reach the seasonal shift. But having installed winter tires in October, with the first frosts, you should check the pressure a couple more times: when the temperature drops to minus ten, fifteen, and when it goes over minus twenty. But from the middle of winter until the moment of changing the wheels to summer ones, there is again a period of relaxation.
Electronics are increasingly thinking for us. Now, a tire pressure monitoring system is being installed on parts of production cars. Moreover, some simply read the wheel speeds through the ABS sensors: after all, a flat tire rotates faster, since its radius is smaller than that of inflated wheels. There are also sensors that evaluate the amount of air pressure and send information via radio to the "brains" of the car. Such devices can also be purchased separately: sensors - in the wheels, and the receiver - in the car.
By the way, a lot depends on the road you are going to take.
The operating instructions supplied with the vehicles indicate that it is recommended to increase the pressure by 0.2-0.3 bar before driving for a long time on expressways. We advise you to follow these recommendations on all cars: it will not get worse.
The operating instructions supplied with the vehicles state that it is recommended to increase the pressure by 0.2-0.3 bar before driving for a long time on highways. We advise you to follow these recommendations on all cars: it will not get worse.
I don’t want to discuss overload: this, you see, is not the case. But, unfortunately, many deliberately overload the car several times a year, not only stuffing the interior and trunk to the eyeballs, but also attaching a trailer, which additionally loads the rear wheels of the tractor. In such cases, we advise you to increase the pressure in the rear tires by at least 0.2–0.3 bar. Tires will only thank you.
If you doubt the accuracy of your pressure gauge, then we advise you to check it immediately after leaving the tire shop, where you were set the obviously necessary pressure, to measure it with your own measuring device (separate or as part of the compressor). So you determine whether your pressure gauge is "lying" a lot. For the future, right on the dial, you can put a mark of the correct value.
Of course, it is better to have your own, known to be correct pressure gauge, but such a toy is not cheap.
Of course, it is better to have your own, known to be correct pressure gauge, but such a toy is not cheap.
If terrible ice caught you on summer tires, say, in the country, and you need to drive some distance along an absolutely icy road by any means, then you should reduce the tire pressure to approximately 1. 6 bar. Is it bad for tires? Yes. But an accident will cost more. In addition, in such a situation, one does not have to wait for high speed, and overheating of tires at near-zero temperatures most likely will not happen.
Everyone knows what caused the excellent maneuverability of Soviet tanks? That's right: wide tracks, that is, low pressure on the ground. We, having an ordinary, non-all-wheel drive car, are also able to provide it with a similar cross-country ability. If the wheels of the car sink into sand, snow or sticky mud, then it makes sense to lower the tire pressure. And not only driving, but also driven wheels.
We know from experience that you can often get out of the "black spot" by reducing the pressure to 1.2 bar.
We know from experience that it is often possible to get out of the "black hole" by reducing the pressure to 1.2 bar.
In a very critical situation, if you know that you have a fairly narrow disc and a relatively wide tire (such a wheel has a lower chance of self-disassembly), you can reduce the pressure to 1. 0 bar.
Stalled on wet grass? Try to relieve pressure.
Stalled on wet grass? Try to relieve pressure.
Pressure reduction is also useful in other cases - for example, to overcome diagonal hanging. If you reduce the pressure in the wheels on which the car rests, their height will decrease and there will be a chance to “hook” on the suspended wheels. Of course, if the car has already laid down on the bottom, then it is too late to reduce the pressure - this will only interfere.
A concrete example of the effect of pressure on flotation. In this case, the pressure is very low, and the contact patch of the wheel with the coating is much larger than that of a conventional car.
A concrete example of the effect of pressure on patency. In this case, the pressure is very low, and the contact patch of the wheel with the coating is much larger than that of a conventional car.
In general, the pressure in tires, as well as in vessels, is better to keep normal. Any deviation has its negative consequences. Tell us, have you ever had to adjust tire pressure to improve flotation?
Tire pressure: your norm
Tire pressure: your norm
See also
Tires are the only vehicle element that is in constant contact with the road. One of the main indicators of their serviceability is pressure. It affects not only fuel efficiency, but also safety.
As a rule, car manufacturers recommend maintaining tire pressures between 2.0 and 2.8 bar. But in practice there are situations when it is necessary to deviate from this norm.
adv. rbc.ru
Tire pressure should be checked at least once a month, there are several ways to do this. We understand why it is so important to observe the optimal pressure indicator and what it affects.
In this story:
Tire pressure is the resistance with which air "presses" on the inner area of the rubber. Properly inflated tires will last longer, give you better ride quality and improve your driving safety. If the pressure in the tires is too low or they are pumped over, then the car owner runs the risk of facing a number of problems: from buying new tires to the threat of an accident.
Properly inflated tires will last longer (Photo: Global Look Press)
Under-inflated tires are tires that are below the recommended pressure. In this case, the contact patch of rubber with the road increases, which leads to increased friction or rolling resistance. A worn out outer edge of the tread can visually give out such a problem.
Increased friction with the road can cause the tire to overheat, slip and even burst. In addition, low tire pressure leads:
When tires are over-inflated, that is, above the manufacturer's recommended rate, the contact patch decreases. As a result, the main friction with the road is taken over by the central part of the tire.
Excessive tire pressure leads to excessive sensitivity to road irregularities and the risk of tire damage, even destruction. Inflated tires also cause the following:
For overinflated tires:
Excessive tire pressure leads to excessive sensitivity to road irregularities and the risk of tire damage (Photo: Shutterstock)
For each car model, the manufacturer sets its own optimal tire pressure. This indicator depends on the mass of the car, the speed of operation, the number of passengers (partial or full boarding), as well as the load on the trunk [1].
The recommended tire pressure can be found in the vehicle owner's manual or on one of the plates/stickers in the passenger compartment. They can be:
Tire pressure is measured in several units. In Russia, they usually indicate in kg / cm 2 (or atmospheres) and bars (bar). These two indicators are almost equal, which is why they are often used as synonyms:
Foreign models often use pounds per square inch (pound per square inch), or psi:
For convenience, car manufacturers can indicate pressure in two units at once - bar and psi. Thus, the need to independently calculate according to the formulas disappears. Otherwise, you can do this in one of the online calculators or check the table of popular values.
| 2.0 bar | 2.1 bar | 2.2 bar | 2.3 bar | 2.4 bar | 2.5 bar | 2.6 bar | 2.7 bar | 2.8 bar |
| 29psi | 30psi | 32 psi | 33 psi | 35 psi | 36 psi | 38 psi | 39 psi | 41 psi |
Temperature has a significant effect on tire pressure: when it drops, the pressure in the wheels decreases with it. When the temperature drops by 10 °C, the tire deflates by an average of 0.07-0.14 bar or 1 to 2 psi [2].
Temperature has a significant effect on tire pressure (Photo: Shutterstock)
Summer tires typically use manufacturer's recommended readings. But in winter, it is advised to add about 0.2 bar to these figures [3].
Experts also recommend checking and correcting tire pressure at outside temperature. In the cold season, swapping is best done not in a warm garage, but on the street. In summer, before such a manipulation, you should make sure that some of the wheels of the car were not under the scorching sun, while others were in the shade.
Sometimes the tire pressure needs to be adjusted according to the situation. For example, when the machine is fully loaded or a trailer is towed. For such cases, automakers, as a rule, separately indicate the optimal pressure.
But there are moments that fall into the category of extreme and non-standard (especially if before that the car most often drove around the city). Automotive expert Tatyana Eliseeva analyzed the most common of them.
Causes tires to heat up, especially in summer, so you should follow the manufacturer's recommendations before such a trip. We do not know what we will meet: patched road repairs or heavy rain. After all, for each of these situations, the recommendations will be opposite. Athletes can play with pressure when track conditions are known and engineers can always change the settings. For a long journey, the layman just needs to choose the average.
Tires must be bled off, especially on sand. The question is for how much? You can bleed up to 0.7 atm, but a not very experienced motorist can slip the wheels with an inaccurate movement, and if the driver turns the steering wheel sharply (for example, trying to catch on the edge of the track), then the tire can come off the disk. And such cases occur regularly.
At near-zero temperatures on packed snow, ice or sludge for new wheels (velcro or studded) it is better to pump the wheels a little so that water and sludge are squeezed out of the central zone of the contact patch and the tread is better have worked. The wheel must be cleared for the tread to work. When it is clogged with snow, the braking distance and traction deteriorate greatly.
If the car has worn wheels, but with an acceptable tread depth for winter tires (4 mm), then you should not hope for the correct operation of the tread. Such a low checker no longer pushes the snow. In this case, it is necessary to reduce the pressure in the wheel, thereby increasing the same contact patch.
Photo: Global Look Press
On a country road, the weight of the machine will be an important factor. In this case, we select the pressure according to the load - specific indicators must be viewed on the central pillar of the body. There you will see something like the following recommendation: the more the car is loaded, the higher the pressure in the rear wheels should be.
But a badly broken road can lead to herniations, ruptures and tire damage. Therefore, if we increase the pressure, then we drive on a bad road as calmly and measuredly as possible. Or we slightly deviate from the manufacturer's recommendations and raise the pressure not as much as the manufacturer recommends.
The main factor in changing the behavior of the wheel is not the pressure difference at altitude, but the presence of a large number of sharp turns and long braking. The tire will heat up not only from the loads, but also from the operation of the brake mechanisms. Therefore, the idea that due to low pressure it is necessary to increase the pressure in the tires is wrong, because the temperature of the wheel has a much greater influence in this case.
The recommended pressure is always given when the tires are cold. This means that the vehicle has not been driven for three hours or has traveled less than 1 mile (or one mile).
There are two ways to check tire pressure: on your own or at a workshop. In the first case, it is enough to use a public pump at a gas station or purchase a pressure gauge. This tire pressure measuring device comes in three types:
Another option is to install special pressure control caps on each nipple. Such a gadget works as follows: the upper part of the cap is transparent and, depending on the level of pressure, an indicator of three colors appears in it. Green - the pressure is normal, yellow - the tire is flat, red - the pressure has exceeded the norm.
Photo: Shutterstock
The easiest way to monitor tire pressure is with the automatic TPMS (Tire Pressure Monitor System). Today, it is installed on almost all models, and in some countries its presence is a prerequisite for releasing a car from the assembly line.
In such systems, the electronics automatically detect changes in the tire, and if the pressure drops below the recommended value, a warning signal lights up on the on-board computer screen.
There are two types of TPMS:
Car manufacturers recommend checking tire pressure every two weeks, but at least once a month. Indeed, even under ideal conditions (for example, the car is idle for a long time), the wheels lose approximately 0.069bar, or 1 psi, per month [4].
The pressure should be monitored before and after a long trip, during a sudden change in temperature (for example, during the first frost or warming), and also after changing tires or driving with a load.
