News of April 04, 2001
GM’s Head Start On Inflation Monitors Keeps Millions In Touch With Their Tires
DETROIT - General Motors Corp. began equipping its cars with tire pressure monitors as early as 1987, and announced that more than 2 million GM cars sold since then have tire pressure monitors – more than any other automaker.
Currently, 14 GM models include tire pressure monitors as standard or optional equipment. GM’s longtime commitment to tire safety predates the new federal requirement to equip new cars and trucks with tire pressure warning systems by late 2003.
The 2000 Transportation Recall Enhancement, Accountability, and Documentation (TREAD) Act, signed into law in November by then-President Bill Clinton, requires the National Highway Traffic Safety Administration to modernize the 30-year-old tire safety standard and to require tire pressure monitors. NHTSA expects to have a draft proposal for an upgraded tire standard ready for review shortly. In addition, written regulations for the tire pressure warning systems are due in November and will take effect two years later.
Proper tire inflation is an important element of safe driving. It always has been. That is why we are way ahead of meeting the tire pressure monitor timetable required by the TREAD Act," said Brook Lindbert, GM’s director of tire-wheel systems group. "With two million GM vehicles already on the road with this technology, I guess you could say we had a head start."
The GM vehicles that monitor tire pressure use either the antilock brake system (ABS) or separate sensors mounted in each wheel. A warning light on the instrument panel or message displayed on the driver information center, along with an audible warning, alerts the driver to check the air pressure in their tires. An estimated 83 percent of tire pressure loss occurs gradually "often without being noticed by the driver.
The ABS system uses the same sensors that communicate with the antilock brakes to measure the difference in rotational speed between wheels. A smaller tire diameter or rolling radius, due to lower tire pressure, will rotate faster. When a tire is at least 10 psi below that of the vehicle’s other tires, the indicator will identify this increased rotation rate as an underinflated tire and signal the driver that a tire needs attention.
With the system that uses sensors mounted in each wheel, pressure is monitored continuously and the system displays a message to the driver when any tire drops six psi below the recommended pressure. An audible warning is also given, and the location of the low tire is displayed.
Once the vehicle displays a low-pressure warning, the driver should allow the tires to cool and then check the tires manually using a pressure gauge. [See the tire safety tips below.] Under- and over-inflated tires should be adjusted to the recommended air pressure for the vehicle.
Tire safety has been an area of focused research by GM for more than three decades, beginning in 1968 with the opening of its Tire and Wheel Systems Laboratory at the Milford, Mich., Proving Ground. The research lab, with its team of 70 engineers and technicians, has allowed GM to mount an ongoing effort to ensure that the original equipment tires on its vehicles perform safely and effectively, from the time the car or truck is driven off the dealership’s lot.
We cannot emphasize enough the important role tires play in highway safety," said Lindbert. "Things like heavy loads, pulling a trailer and weather can affect tire performance dramatically. Most people don’t realize that. They also don’t think about the fact that the entire vehicle is entrusted to just 20 square inches of rubber hitting the road. We don’t take tire safety for granted, and neither should motorists," Lindbert said.
Some tips to keep in mind about tire safety:
The list of 2001 GM models that feature tire pressure monitors as standard or optional equipment:
(April 2, 2001)