A major factor that usually causes tire noise is the air chamber inside the tire. The large void that is filled with air acts as a giant resonance chamber. Thus, the tires are something like donut-shaped drums that generate a low-frequency hum when tires are rolling. Many tires also produce a drum-like noise when impacting minor bumps in the road.
The sound of the tread contacting the road also causes tire noise. Another factor that causes tire noise is the sound of air that is compressed inside the tread grooves. Diverse tread compounds and tread styles cause different levels of noise. Additionally, as the tire tread wears down, the type and level of noise also changes. Treads that are manufactured for off-road driving and heavier loads are louder than those tires designed for smooth rides.
If the tires of a vehicle are not rotated as often as recommended, road noise is sometimes the result. Car owners need to rotate the tires to ensure that all four tires wear evenly. Many manufacturers recommend tire rotation after every 5,000 to 10,000 miles. Lastly, improper inflation causes tire noise. This noise is caused from tires pressing against the road in an uneven pattern.