General Testing

PRESSURE GAUGES
A quality air pressure gauge is recommended to check tire pressure. After checking the air pressure, replace valve cap finger tight.

Fig. 2:

TIRE TREAD WEAR INDICATORS
Tread wear indicators are molded into the bottom of the tread grooves. When tread depth is at 1.6 mm (1/16 inch), the tread wear indicators will appear as a 13 mm (1/2 inch) band across the tread groove in the tire.

Tire replacement is necessary when wear indicators appear in two or more tread grooves or if localized balding occurs.

TIRE NOISE AND VIBRATION
Radial-ply tires are sensitive to force impulses caused by improper mounting, vibration, wheel defects, or possibly tire imbalance.

To find out if tires are causing the noise or vibration, drive the vehicle over a smooth road at varying speeds. Note the effect of acceleration and deceleration on noise level. Differential and exhaust noises will change in intensity as speed varies, while tire noise will usually remain constant.