It is tough for a technician to know what they are getting when they buy a rotor. According to a recent U.S. International Trade Commission report, 80% of the rotors sold today are made in a country other than the United States. If the technician or counterman is only going on the price on the screen, it is difficult to pick the best rotor.

Design and Engineering
Some rotor manufacturers care only about the external dimensions of a rotor. The engineer wants it to fit and disregards the performance attributes. In the industry, this is called the “round and heavy” philosophy. Some aftermarket rotor manufacturers will take the OE design and make it better in order to exceed customer expectations.

Engineers will put in years of research and development and racing in order to develop and manufacture a rotor that can go beyond OE specifications.

Some rotor manufacturers will research and formulate high temperature and high strength alloys in order to have the best metallurgical microstructures. Also, they will develop casting and machining processes that maximizes certain properties of the metallurgical microstructures.

Casting and Machining
Many cheap castings are poured with the least amount of iron possible. When these are machined at the factory, they are essentially performing a “skin cut” where they remove the least amount of scale and material possible. The outer layer...

Click here to read the rest of the article at Tire Review