What are Genuine Service Parts?
Genuine GM parts are GM’s version of OEM parts. Short for “original equipment manufacturer,” OEM parts are products produced directly by the manufacturer of your vehicle’s original components, and are thus identical to the parts of your car that you are replacing. Genuine GM parts are brand new and constructed from the same quality materials as the original components of your car. In other words, they’re designed from the get-go to fit your GM vehicle.
Aftermarket parts, on the other hand, are manufactured to approximate your vehicle’s original parts but are often made from different or lower quality materials and come with little guarantee of compatibility.