Tire Pressure Monitoring Systems

[Luke@tirerack]

GM Cars An Update on Tire Pressure Monitoring Systems and Aftermarket Wheels A direct tire pressure monitoring systems (TPMS) will be standard equipment on every vehicle sold in the U.S. after September, 2007. The criteria for TPMS standardization is that the vehicle must have only four wheels (no dual-wheeled trucks or motorcycles), and weigh less than 10,000 lbs. GM has used TPMS since the 1987 Corvette hit the streets. They started with the direct strap-style system on the C4 and transitioned to a direct valve sensor TPMS (see TPMS Facts below) on the C5 and C6. Wheels can be swapped with ease, as most GM sensors can be recalibrated with a high-powered magnet available at most hardware stores. Other GM vehicles are equipped with an indirect TPMS that requires several steps and a little bit of straight-line driving to reset it. All GM valve sensors are currently being produced by Schrader, Siemens, or TRW. The Tire Rack carries all three. With the exception of the early C5 Corvette's large sensors, sensor size shouldn’t be a problem with most wheels. Wheel manufacturers are aware of the large sensor issue and are rushing to get most of their wheels TPMS-compatible. The Tire Rack's fitment specialists have carefully determined which wheels that are currently available will be compatible with the system installed on your vehicle. : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : If you have any questions about the wheel you're considering, call or post your question for confirmation that it will be compatible with your TPMS. : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : TPMS Facts Direct TPMS use a sensor in the wheel/tire to wirelessly relay pressure back to the driver via a display inside the vehicle. Some vehicles have a digital screen that continuously shows all four tire pressures (five if spare has sensor). Others simply flash a "low tire pressure" light on the dash. Additionally, there are two different styles of sensors for a direct system: a valve sensor and a strap/band sensor. Only valve sensors are used on current GM direct system-equipped vehicles. If you bought an aftermarket SmarTire TPMS, its sensors are held on by a strap around the barrel of the wheel. Indirect systems work in conjunction with the ABS wheel speed sensors that “count” the number of revolutions of each tire. If the right front tire is low (25psi) it will spin faster than the left front tire (35psi). The ABS system will recognize this change and alert the driver with a flashing light and possibly a loud chime. GM's indirect systems do not affect the fitment of aftermarket wheels.