Back to all

The Truth about Tire Pressure (Tire Inflation)

May 19, 2024

Most light vehicles (under 10,000 pounds/4,500 kg) in North America sold from 2008 model year on have a feature that many people are confused about.  It's the tire pressure monitoring system (TPMS).  You may have some experience with it yourself if you own a newer vehicle.  Vehicles with TPMS have sensors in each tire that are supposed to warn the driver when tire pressure gets dangerously low.  That's important because tires that are significantly under-inflated can cause very serious accidents.

Unfortunately, many drivers think the TPMS does all the work keeping track of tire pressure. To them, as long as the warning light or gauge isn’t giving a warning, the tires must have the proper amount of air pressure in them.  That's not the case.

Tire pressure monitoring systems aren't all created equal.   Some give you a digital readout of the pressures in each individual tire.  But many simply have a warning light that looks like the cross section of a tire with an exclamation point in the middle.  If you don't know what it is, it's because it's not instantly recognizable as a tire.  In fact, one company that makes TPMS, Schrader Performance Sensors, surveyed drivers.  Their study showed that more than 40 percent of drivers didn't know that that warning light was. 

One out of 5 of the drivers who did know what the light was only looked at their tires after the light came on to see if they could see any that needed air; they never checked them with a tire gauge or had someone else do it.  Ten percent of them didn't do anything when the light came on.

In most vehicles with TPMS, the warning comes on only when the tires are more than 25% underinflated.  The American Automobile Association says that's under the pressure you need for safe vehicle operation.

The bottom line is once a month you should make sure your tires are inflated to the manufacturer's recommendations.  That means each tire should be measured with an accurate, external tire gauge.  To be confident you are getting a correct reading, take your vehicle to a reputable service facility where their equipment is calibrated and they know what they're doing.

Severely underinflated tires can contribute to an accident that kills or severely injures people.  The idea behind TPMS is well intended, but the system was never meant to replace regular inflation measurements and maintenance.  Periodically have your tires checked for proper inflation.

Tuffy Tire & Auto Service Center Appleton
2940 E. College Ave.
Appleton, Wisconsin 54915
920-954-8500

More articles from Tuffy Appleton

Give it the Boot (Ball Joint Boot Replacement)

June 29, 2025

Your vehicle may be wearing boots right now and you might not even know it. They're called ball joint boots. They're actually protective, flexible things that protect parts of your suspension (called ball joints) from all the hazards the road can fling at them. If one of those ball joint boots... More

Let?s Shift Gears (Transmission Fluid Replacement)

June 22, 2025

If you have a vehicle with an automatic transmission, you probably never think about gear shifting. When motor vehicles were invented, all of them had to be shifted manually. But that wonderful self-shifting transmission, referred to these days as simply an automatic, changed everything. Automa... More

Putting a Stop to Brake Problems (Brake Service)

June 15, 2025

It's safe to say that most drivers take their brakes for granted. You press on the brake pedal and the vehicle slows down or stops. It's easy to see why it is so important for your vehicle's brakes to be working correctly. Brakes are an important safety feature of any vehicle. When it comes to... More