Aftermarket parts are the parts used for replacement purposes in the vehicle that are not manufactured by OEM (Original Equipment Manufacturer). Aftermarket parts might come cheap, but using them can’t be entirely risk-free. Its usage in the vehicle can alter the coverage of an insured item. The availability of untested aftermarket parts can cause performance issues down the road. The quality of aftermarket parts always remains questionable. Thus, it is recommended to use OEM parts during the replacement.