Saab 2007 High speed operation, When to check, How to Check, Tire Inspection and Rotation

Car care and technical information 223

High speed operation

WARNING

Driving at high speeds, 100 mph

(160 km/h) or higher, puts an additional strain on tires.

Sustained high-speed driving causes excessive heat build up and can cause sudden tire failure. You could have a crash and you or others could be killed. Some high-speed rated tires require infla- tion pressure adjustment for high speed operation. When speed limits and road conditions are such that a vehicle can be driven at high speeds, make sure the tires are rated for high speed operation, in excellent condition, and set to the correct cold tire inflation pressure for the vehicle load.

When to check

Check your tires once a month or more.

Don’t forget your compact spare tire. It should be at 60 psi (420 kPa).

How to Check

Use a good quality pocket-type gauge to check tire pressure. You can’t tell if your tires are properly inflated simply by looking at them. Radial tires may look properly inflated even when they’re underinflated.

Be sure to put the valve caps back on the valve stems. They help prevent leaks by keeping out dirt and moisture.

Tire Inspection and Rotation

Tires should be rotated every 10,000 miles (16 000 km).

Any time you notice unusual wear, rotate your tires as soon as possible and check wheel alignment. Also check for damaged tires or wheels. See “When It Is Time for New Tires” on page 224 and “Wheel Replacement” on page 227 for more infor- mation.

The purpose of regular rotation is to achieve more uniform wear for all tires on the vehi- cle. The first rotation is the most important.

When rotating your tires, always use the correct rotation pattern. Left front tire to left rear. Left rear tire to right front. Right front to right rear. Right rear to left front.

Don’t include the compact spare tire in your tire rotation.

After the tires have been rotated, adjust the front and rear inflation pressures as shown on the Tire-Loading Information label. Make certain that all wheel nuts are properly tight- ened. See page 238.

WARNING

Rust or dirt on a wheel, or on the parts to which it is fastened, can make wheel nuts become loose after a time. The wheel could come off and cause an accident. When you change a wheel, remove any rust or dirt from places where the wheel attaches to the vehicle. In an emergency, you can use a cloth or a paper towel to do this; but be sure to use a scraper or wire brush later, if you need to, to get all the rust or dirt off. See “Changing a wheel” on page 236.