Get Ready for Tire Pressure Monitoring Systems

You may already have a tire pressure monitoring system. For many people, it’s not a bad idea, because under-inflated tires account for roughly 20% of all tire failures, and have been attributed to some 10,000 plus vehicle accidents. Of course, simply checking tire pressure (on a cold tire) and making adjustments as needed could do away with a lot of the trouble. Still RVers aren’t unlike most drivers: Some are conscientious about keeping an eye on things, while others . . .

It is with the latter folks in mind that the federal government has minted a new law: Beginning in 2006, some autos and light trucks (typical RV fifth wheel and travel trailer haulers) began rolling off the assembly lines with automated tire pressure monitoring systems. It’s been a gradual phase-in, but starting with the 2008 model year, all new vehicles must have the system. Simply stated, if a tire has low air pressure, you get an “idiot light” on your dash to let you know you need to pump it up. It’s a largely set it and forget it system, requiring little attention on our part.

It’s when the tire needs servicing that pressure increases–not in the tire–but in the mind of the owner. If Joe Schmoe down at the tire shop isn’t careful, he can damage the tire pressure sensor/transmitting unit. How so? Well, there’s no universally accepted “system” in place for where and how the sensor transmitters are placed. Some are banded on the tire rim, inside the tire, others might be attached to the valve stem and rim. If the tire “technician” damages the sensor, all bets on accurate data are off. With that in mind, be sure to always REMIND the tire shop folks that your vehicle is equipped with the sensor system and to use caution when servicing your wheels.

Thinking about changing to a different tire style or profile? Best to check your vehicle owner’s manual first. There are some instances where tires that might otherwise “work,” won’t because of the tire pressure monitoring system.

Most tire pressure transmitters are battery powered. Thankfully, Detroit and other manufacturers are using batteries with a lifespan of 7 to 10 years. Nevertheless, when the batteries are shot, they’re not reusable. Add one more player to the act: The addition of 65 million batteries to the waste or recycle stream every year, once they start dying off.

Does having this automated system mean you can throw away your tire gauge and buzz past the air pumps? Since the law only mandates an alarm signal when tire pressures drop below 25% of the recommended inflation rate, on a 65 psi truck tire, you could be down to 49 psi before your dash light revs up. While fuel economy might not be dramatically affected, that kind of pressure loss could certainly affect your tire wear. And with prices of tires today, our money is on regularly checking with a gauge, regardless of whether we have a monitoring system or not.

Illustration courtesy Subaru