I totally disagree with Tire Business' Sept. 16 editorial favoring the use of so-called ``direct'' air pressure monitoring systems. In those systems, electronic sensors mounted within each tire transmit information by radio to a receiver inside the vehicle.
I prefer ``indirect'' systems that use the vehicle's anti-lock brake system to detect changes in wheel rotation speed.
BMW A.G. and a few other auto makers currently use an ABS Tire Circumference Monitoring System and it works great. Equally important, any repair or maintenance of such systems is being carried out by the new-car dealership and not the tire dealer or other independent service provider.
Valve-stem or interior-mounted monitors are a pain-just ask your best tire tech. Servicing tire sensors usually is carried out by manufacturer-trained ``technicians'' or the daring tire tech who broke one-at a cost of $100 apiece, provided you can locate a used version.
Other problems that can plague such sensors include the:
* Infamous flat tire on the side of the road;
* Catastrophic tire failure that occurred because the last guy who changed the tire broke the sensor and didn't tell his boss. (It was the third such incident that month and it occurred because the owner was too cheap to replace his outdated pre-1980s tire changer.);
* Ruining the sensor by installing flat-proofing foam;
* Likelihood that tire rotation won't be carried out unless the car owner is willing to pay an arm and a leg to rotate the sensors;
* Inability of pressure sensors to be installed properly in some aftermarket wheels whose contours won't permit their installation close enough to the drop-center; and
* Limited battery life, lasting five years at most.
In the meantime, ask your tire tech if he knows how to get the computer in that Corvette he just changed the tires on to ``relearn'' the position of the sensors. Yes, there now are instructions on the Internet-three years too late. But a laptop computer and software are necessary to program some makes and models of sensors.
In my capacity as a firefighter and rescue worker as well as the owner of a one-man tire business, all the rollover accidents I have been called to involved vehicles that were three years old or older and in very poor maintenance.
If we, as an industry, are to look out for customer safety and provide good service, it should be for the owners of all cars-not just those five years old or less.
We had better think long and hard about the decision the National Highway Traffic Safety Administration (NHTSA) is going to make in regard to the air pressure monitoring systems mandated by Congress. Government agencies don't easily admit their mistake and change once they have made a poor choice.
If NHTSA decides in favor of direct monitoring systems, all newer cars, trucks and sport-utility vehicles will need to go back to the auto dealership for service-affecting businesses ranging from car rental agencies to fleet-maintenance companies. No single device or computer system will be available for reprogramming these devices.
Think about it, talk about it-your business may depend on it.
The lowest-paid worker in your shop ultimately is going to have to do battle with those sensors. (Mechanics beware, you may find yourselves slinging tires. Those in the OEM shops already are doing so for liability reasons.)
Go to a better solution-the ABS system. Your customers will appreciate it and so will your employees.
Craig J. Knarich
Owner-operator
ETS Tire Service
Palm Harbor, Fla.