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Interpretation ID: 7871

Mr. Michael J. Motzkin
Pioneer Plumbing
Post Office Box 35833
Tucson, AZ 85740-5833

Dear Mr. Motzkin:

This responds to your letter of October 14, 1992 regarding Federal requirements pertaining to brake specifications. In particular you asked whether there are any regulations requiring automotive brake drums and rotors not to be milled beyond manufacturer specifications, and whether manufacturers are required to stamp their specifications on brake drums and rotors. I am pleased to have this opportunity to explain our law and regulations for you.

The National Traffic and Motor Vehicle Safety Act of 1966 (Safety Act) authorizes the National Highway Traffic Safety Administration (NHTSA) to issue Federal motor vehicle safety standards for new motor vehicles and new motor vehicle equipment. All motor vehicles and items of motor vehicle equipment manufactured or imported for sale in the United States must comply with all applicable safety standards. This agency does not provide approvals of motor vehicles or motor vehicle equipment. Under the Safety Act, the manufacturer is responsible for certifying that its motor vehicles or equipment meet applicable standards.

NHTSA has issued a number of safety standards which specify performance requirements for new motor vehicle brake systems and certain new brake equipment. The standards do not require manufacturers to stamp specifications on drums or rotors, although it is common practice for manufacturers to do so.

The Federal motor vehicle safety standards do not apply to a motor vehicle after its first sale to a consumer. However, manufacturers, distributors, dealers, or motor vehicle repair businesses modifying a used vehicle are prohibited by section 108(a)(2)(A) of the Safety Act from knowingly rendering inoperative any safety device or element of design installed on or in a motor vehicle or item of motor vehicle equipment in compliance with a safety standard. The milling or turning of brake drums and rotors is typically performed during the course of repairing a used vehicle with worn brakes. We do not believe that the "render inoperative" provision would ordinarily be relevant to such a situation.

The states may regulate the repair of motor vehicles. We suggest you investigate the laws of Arizona to see whether they affect your situation.

I hope this information is been helpful. If you have any further questions about NHTSA's safety standards, please feel free to contact David Elias of my staff at this address or by telephone at (202) 366-2992.

Sincerely,

Paul Jackson Rice Chief Counsel ref:105 d.12/14/92