Michigan Governor Rick Snyder has vetoed state legislation that would have placed new restrictions on the use of non-OEM replacement parts by automotive repair shops.

House Bill 4344, which sought to update the state’s Motor Vehicle Service and Repair Act, included provisions restricting the use of non-OEM replacement parts during a vehicle’s original manufacturer’s warranty or during the first five years of that warranty — whichever is less.

Repair garages and body shops would have needed to ensure that major component replacement parts were either new or used OEM parts or were aftermarket parts verified as OEM-level quality by the Certified Automotive Parts Association, NSF International, or another nationally recognized testing agency. An exception to this mandate would have required a customer to sign a waiver.

In a letter explaining his veto, Snyder cited concerns about the legislation’s potential impact on the aftermarket parts industry and its ability to compete with original equipment manufacturers.

“As Michigan continues its comeback and continues to be a leader in promoting new technology in the automotive industry, it is imperative that we ensure all components of that industry remain strong, including Michigan’s robust aftermarket parts industry,” Snyder said in the letter. “I am concerned about HB 4344’s effect on market competition for replacement parts on motor vehicles.”

Snyder also argued that the legislation’s language failed to adequately delineate between automotive parts designed for safety rather than aesthetics, and that such a law would have limited the use of safe, high-quality aftermarket parts designed for particular vehicles.

Further, Snyder speculated that a loosening of competition in the replacement parts market could result in higher insurance rates for vehicle owners.

“Enacting a law to prohibit mechanics from providing high quality and safe alternatives for customers is an inappropriate impediment on the competition that has resulted in both high quality OEM and aftermarket parts for Michigan drivers to enjoy,” Snyder said.