Onboard tire-pressure monitors help keep your vehicle's tires safe

Onboard tire-pressure monitors and clearer tire-labeling requirements for new vehicles are among the provisions of the Transportation Recall Enhancement Accountability and Documentation (TREAD) Act passed after Firestone's 2000 tire recall.

A revised doorjamb placard with clearer inflation specifications and other information is now required for all new vehicles. Upcoming rules are also likely to require a phase-in of onboard tire-pressure monitoring systems for all new vehicles. But some such systems work better than others, and the government hasn't settled on which to require.

Consumer Reports and other groups have called for monitors that use wheel-mounted sensors to give direct readings for each tire. Such systems are a step above indirect monitors, which use the antilock brake system to compare revolutions among all four wheels. While indirect systems cost less to install, they may not warn you if all tires lose pressure equally.

Even the most effective tire-pressure monitors can't compensate completely for poor tire maintenance. Here's how to help keep your tires as safe as possible:

Do your own pressure checks. Overinflated tires ride harshly and wear unevenly. Underinflated tires also wear unevenly, handle poorly, and may flex excessively, causing overheating and possible failure. Tires lose roughly 1 pound per square inch of pressure for every 10° F drop in outside temperature. They also lose air over time; pressure loss was as much as 13 pounds per square inch per year in our tests of passenger-car all-season tires. Check pressures at least once a month when a vehicle has sat for at least one hour and tires are cool; pressures should match those on the vehicle placard.

Inspect the sidewalls and tread. Cuts or bulges are signs of impending failure; replace such tires. Check the tread periodically with a tread-depth gauge; uneven wear may mean improper wheel alignment or worn suspension parts. Rotate tires every 6,000 to 8,000 miles or as advised in your owner's manual to help equalize wear between front and rear.

Replace all four tires at once. Many drivers replace only two tires at a time if the other two appear sound. We believe the risks aren't worth the savings. Replacing only the front tires increases the chance of fishtailing at the rear. Replacing the rear tires alone denies you the added resistance to hydroplaning you're likely to get by mounting new tires up front.

source:consumerreport