A British thermal unit (Btu) is a standard unit of energy that is used in the United States and sometimes in the U.K.
There is another defect in tires that can cause a vibration called loaded road force variance. The tires and pass a visual inspection, a radial and lateral runout test, be perfectly balanced, but still cause a vibration. This is due to the internal defects in the tire.
1 Tire Damage â We often over look our tires and we seldom check for problems or damage. 2  When tires are worn out we sometimes see BALD PATCHES, EXPOSED WIRES or BULGE PATCH, these cause vibration when reaching a certain speed.