The five conditions you'll see
When sellers respond to a parts request, they specify the condition of what they're offering. Five come up regularly.
OEM new is a genuine factory part, unused. This is what a dealership sells. Highest price, guaranteed fit.
OEM used is a genuine factory part pulled from a salvage vehicle. Same engineering as OEM new at a fraction of the cost. Condition depends on mileage and how it was pulled.
Aftermarket new is a new part made by a third-party manufacturer. Quality varies widely by brand and part type.
Aftermarket used is a used third-party part. Cheapest option, usually only practical for body panels or other non-critical components.
Remanufactured is a used core that's been rebuilt to spec. Common for transmissions, alternators, starters, and brake calipers. Typically comes with a warranty.
When OEM matters
For safety-critical parts, sensors, modules, and anything where fitment precision is non-negotiable, OEM (new or used) is worth the premium. A used OEM airbag module from a low-mileage car is a different product than an aftermarket one from an unknown factory.
For body panels, brackets, and trim pieces, aftermarket new is often fine. The quality gap between OEM and a decent aftermarket bumper cover is small for most drivers.
For wear items like brake pads, filters, and belts, aftermarket is the standard choice. Most reputable aftermarket brands meet or exceed OEM specs for consumable parts.
The aftermarket quality problem
Aftermarket isn't one thing. Gates makes timing belts that are arguably better than OEM. A generic offshore brand might not make it through the warranty period. The brand matters more than the category.
When a seller says "aftermarket new" without naming the brand, that's worth asking about. "Aftermarket new, Dorman" is usable information. "Aftermarket new" with nothing else is a reason to ask before buying.
Remanufactured is often the smart middle ground
For major components like alternators, power steering pumps, and transmissions, remanufactured is worth considering. You get a warranty, the unit has been bench-tested, and the cost is typically 30-50% less than new OEM. On a transmission, that spread can be $400 to $1,500 on the same application.
Comparing options side by side
When you post a request on AnyPartsHub, sellers quote the condition they have in stock. You can see OEM used, aftermarket new, and remanufactured options on the same part from different sellers. Having everything in one place makes the decision straightforward. You can also browse car and SUV parts sellers by category.