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In the past, many different remedies have been tried to eliminate the sources of annoying brake noise, e.g., replacing brake hardware, adding shims, resurfacing the rotors, etc. The composition of the brake linings was seldom considered, since asbestos-filled materials possess many characteristics important to low noise operation. With the disappearance of asbestos from brake linings, many other materials were evaluated in order to maintain performance while keeping brake noise to a minimum. Fillers like calcium silicate, glass fiber, mica, etc. offer some similar performance characteristics to asbestos. Friction modifiers, such as metal oxides, metal sulfides, rubber scrap, etc are also used to maintain a more constant coefficient of friction during braking. Among the metal sulfides, molybdenum disulfide (MoS2) is often used since it possesses very good dry lubricating properties.

Ever since the introduction of friction brakes in vehicles, brake system designers have been striving to improve braking performance. To meet this growing demand for better brakes, lining manufacturers have evaluated numerous additives in their material formulations. These additives provide several different technical properties, the foremost being safety-related features such as frictional stability and resistance to fading. In more recent years, brake noise has become important with the elimination of asbestos fibers in linings, and there is now also a need for a higher frictional coefficient to offset increases in overall vehicle weight. Prolonging the service life of brake components, reducing pad wear, and minimizing rotor wear caused by DTV (Differential Thickness Variation) are other issues that face lining manufacturers.