2004 Lexus IS 300 Owners Manual - Page 385

03 07.09 CHASSIS The effectiveness of snow tires is lost if the tread wears down below 4 mm (0.16 in.). If you have tire damage such as cuts, splits, cracks deep enough to expose the fabric, or bulges indicating internal damage, the tire should be replaced. If a tire often goes flat or cannot be properly repaired due to the size or location of a cut or other damage, it should be replaced. If you are not sure, consult with your Lexus dealer. If an air loss occurs while driving, do not continue driving with a deflated tire. Driving even a short distance can damage a tire beyond repair. Any tires which are over 6 years old must be checked by a qualified technician even if damage is not obvious. Tires deteriorate with age even if they have never or seldom been used. This also applies to the spare tire and tires stored for future use. Tire selection When replacing a tire, use a tire of the same size and construction, and the same or greater maximum load as the originally installed tires. Using any other size or type of tire may seriously affect handling, ride, speedometer/odometer calibration, ground clearance, and clearance between the body and tires or snow chains. Check that the maximum load of the replaced tire is greater than 1/2 of the Gross Axle Weight Ratings (GAWR) of either the front axle or the rear axle, whichever greater. As for the maximum load of the tire, see the load limit at maximum cold tire inflation pressure mentioned on the sidewall of the tire, and as for the Gross Axle Weight Ratings (GAWR), see the Certification Label. For details about the Certification Label and sidewall of the tire, see pages 316 and 352. 366