1. (Units) a unit of heat in the fps system equal to the quantity of heat required to raise the temperature of 1 pound of water by 1Â°F. 1 British thermal unit is equivalent to 1055.06 joules or 251.997 calories.
Quick Answer. 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.
Likes Received: 74. I've been having problems with excessive tire noise coming from the rear for some time. My local mechanic looked at it and suggested wheel balance because it looked like rear passenger tire was wearing unevenly and thought it might be the source of road noise. It looks like he was partially right.