I used to think that tire pressure is not that important. I often neglected my tires, not thinking about the consequences. It all changed when I talked with a tire specialist over at a local shop. He said:
”It’s very important to monitor your tire pressure. Inaccurate tire pressure can increase your gas mileage, can cause your tires to wear faster and can affect the grip and handling. This is something that you can fix very easily by installing a tire pressure monitoring system, if you already don’t have one.”
Most of the cars manufactured after 2012 are equipped with tire pressure monitoring systems, but this feature is much more rare on older cars. Fortunately, there’s a clever and easy solution for You can order a tire pressure monitoring system (see on Amazon.com) and install it by placing a pressure transducer at each tire. Then, this information is wirelessly sent to a receiver unit which plugs into the power outlet and displays each tires pressure. The tire pressure monitoring system can even inform you if you have an air leak. Here are the top 3 reasons why you should monitor your tire pressure and some bonus tips:
How Tire Pressure Affects Handling – Grip
So how does tire pressure affect grip? Well, let’s say you’re on a track day and it’s sunny and dry. In this case, it can be beneficial to decrease your tire pressure because you can get a larger contact patch and as a result more grip. That being said, the complete opposite can happen in the wet. So, here we’re going to be talking about hydroplaning.
Take a look at the first example in the upper left corner. We’ve got our tire here and it’s traveling and there’s water on the ground which piles up in front of the tire and that tire has to move that water out of the way in order to maintain grip with the ground. So, hydroplaning occurs when the average pressure of the tire on the ground is equal to the average pressure of the water pushing back up on that tire. That makes sense because if they’re equal it means it’s basically going to be floating. So, now keeping that in mind a tires pressure will directly affect its average pressure it’s putting down on the ground. So, if you increase the tire pressure, you’re going to increase the amount of pressure on the ground because you’re going to decrease the contact patch and you’re gonna have more pressure on that area. So, there’s a direct link between your tire pressure and the likelihood of your car to hydroplaning. The higher your tire pressure, the lower the likelihood of you are to hydroplane, and the lower that tire pressure it significantly increases the chances of you hydroplane.
So, what does this actually look like is shown on the second example in the bottom left corner. If you’re looking at the front of the car and you’ve got the correct tire
pressure on the left. You can see that that water will move outside around it, and you also have treads which you can move through. But, if you have too low of a tire
pressure you’re going to start resting on the outside edge and you’ll have this kind of concave area where the water starts to flow underneath the tire as shown in the right-side picture, because the pressure is too low and it builds up underneath there and you can begin to hydroplane.
You can also look at this from a perspective of the contact patch as shown in the bottom right side example. So, if you’re looking down on the contact patch, if you have a properly inflated either one of the options where it can flow around here, it may be more difficult for it to flow around. But, that’s why you’re going to have treads and things like that so the water can pass underneath, but if you know it’s too deflated that tire is a really low tire pressure, you can see that contact patch will start to push to the outside of the tire and you can have that water flow underneath. So, it’s very important to maintain a decent tire pressure.
How Does Tire Pressure Affect Fuel Economy
In order to understand that we need to understand rolling resistance. So, rolling resistance is the energy lost as heat when a tire deforms. So, it’s compressed and then it stretches back out(see image on upper left corner) and in that deformation that loses some of that energy as heat and that’s rolling resistance and that’s going to be a force that your car has to overcome in order to drive. So, there’s actually a very strong relationship between rolling resistance and the pressure and your tire, and it’s actually an exponential function. As you decrease the amount of rolling resistance, you have exponentially increases (see down left corner).
Michelin did a study (see example down-right corner) and they reduced the tire pressure of a tire by one bar or 14.5 psi from what the manufacturer had set it at, and they noticed a 30% increase in the rolling resistance, and this equates to about a three to five percent greater amount of fuel consumption. As I mentioned this only gets worse, so as you keep continuing to decrease pressure you exponentially gain a rolling resistance and that means you exponentially gain how much fuel consumption you’re going to have.
How Does Tire Pressure Affect Tire Wear
For this example, I will be showing you 3 different scenarios with a properly inflated tire, over-inflated tire and an under-inflated tire.
Looking at each of these, with the properly inflated tire you’re going to have even wear and you’re gonna have a nice contact patch. An over-inflated tire you’re going to have more pressure on the center of the tire and as a result you’re going to wear down that center strip and have wear on the center of the tire rather than an even distribution of the wear. With an under-inflated tire you’re actually going to have increased pressure on the outsides of the tire on the edges and so as a result you’re going to wear out those edges first on that tire.
Best Tire Pressure Monitoring Systems
#1 RV 6-Tire Flow-Through Sensor Tire Pressure Monitoring System (TPMS) (See on amazon.com)
Has a replaceable battery on the flow-through sensor.
The portable monitor which will be located in your cabin also has a replaceable battery.
It monitors PSI from 0-199.
Up and running 24/7.
Can show air leaks.
#2 DEEWAZ TPMS Tire Pressure Monitor System, Solar Wireless Tires Pressure Monitoring Systems (See on amazon.com)
Solar panel with mono-crystalline silicon.
800mAh with SEIKO monitor battery which requires charging once per year.
Frequently Asked Questions About Tire Pressure Systems
How Tire Pressure Sensors Work
Like I said earlier, almost all modern cars are equipped with a tire pressure monitoring system or TPMS. If not, you can get one on amazon.com.
The TPMS is designed to alert the driver of significantly low pressure in one or more of the tires. Many TPMS systems use sensors inside the wheels to determine if the tires are inflated to proper specification. When the air pressure in a tire drops a certain amount below specification, an indicator is illuminated on the vehicles instrument panel. The TPMS sensors are powered by a small internally sealed battery that provides an operational life of seven to ten years. Because the battery is not separately replaceable, the sensors must be replaced when the batteries are near the end of their life. When the battery charge becomes too low, the TPMS indicator on the vehicle’s instrument panel will illuminate indicating a failure in the TPMS system. In this stage the system no longer will monitor tire pressure and the driver will need to increase the frequency of their manual checks of each tires pressure and condition. If the TPMS indicator illuminates in your vehicle, make an appointment with your local dealer to have the TPMS serviced. Dealers may also use a TPMS tool to determine the remaining battery life for each of the sensors. If one or more of the batteries are found to have a low charge, the dealer may recommend replacement of all four sensors to avoid multiple dealer visits. Dealers make this recommendation because
if one battery has a low charge, it’s likely the other batteries are nearing the end of their operational life.
Are Tire Pressure Sensors Wireless
Yes. The tire pressure monitoring system work by sending data wirelessly from the sensors to the monitor placed in your cabin. Each sensor has a unique code which feeds your monitor.
Can Tire Pressure Sensors Be Repaired
Yes. Some shops offer TPMS repairs, but the repair will probably cost almost as buying new tire pressure monitoring system. However, if the battery in the TPMS is dead, you will have to change the whole system.
Can Low Tire Pressure Cause Vibration
I am sorry to bring you the bad news but yes, low tire pressure can cause your vehicle to vibrate at high speeds. If your tire pressure is correct, than you should check if your tires are balanced correctly. Also, make sure that your vehicle has the correct tire setup and you are not driving with over sized tires.
Can The Weather Impact My Tire Pressure?
This is a well known fact. Changes in the weather can cause your tire pressure to go up and down. If the weather is colder, your PSI can drop temporarily. If the weather is hot, this can cause your PSI to increase. You should check your tire pressure before every season and inflate or deflate your tires accordingly.