2011 Chevrolet Impala Owner's Manual - Page 312

10-56 Vehicle Care . Tire Inspection GM recommends that the tires, including the spare tire, if the vehicle has one, be inspected for signs of wear or damage at least once a month. Replace the tire if: . The tire has a puncture, cut, or other damage that cannot be repaired well because of the size or location of the damage. See When It Is Time for New Tires on page 10‑57 and Wheel Replacement on page 10‑63. Tire Rotation Tires should be rotated every 12 000 km (7,500 mi). See Scheduled Maintenance on page 11‑2. The purpose of a regular tire rotation is to achieve a uniform wear for all tires on the vehicle. This will ensure that the vehicle continues to perform most like it did when the tires were new. Any time you notice unusual wear, rotate the tires as soon as possible and check wheel alignment. Also check for damaged tires or wheels. The indicators at three or more places around the tire can be seen. There is cord or fabric showing through the tire's rubber. The tread or sidewall is cracked, cut, or snagged deep enough to show cord or fabric. The tire has a bump, bulge, or split. . . When rotating the vehicle's tires, always use the correct rotation pattern shown here. Do not include the compact spare tire in the tire rotation. .