Genuine, OEM or aftermarket? The difference and when to choose each

The first question you face when ordering a part: genuine or aftermarket? And there's a third option you hear about a lot: OEM. The difference isn't just price, and the right choice depends on the part itself and where it will work.

Genuine

A part carrying the machine maker's name, logo and part number, sold through the dealer or its distributors. Guaranteed to match the specification, at the highest price.

OEM (original equipment manufacturer)

Many machine makers don't manufacture every part themselves. A filter, sensor or belt, for example, is made by a specialist factory and printed with the machine maker's logo. The same factory sells almost the same part under its own brand (such as Donaldson, Fleetguard or Bosch). Quality is usually very close to genuine, at a lower price.

Aftermarket

A part from another manufacturer designed to fit in place of the original. There are excellent aftermarket parts and poor ones, and the gap between brands is large. A good aftermarket part is a smart choice for many items.

When to choose each

• Critical parts that are costly if they fail (injection pump, injectors, internal engine parts, ECU): genuine or trusted OEM.
• Filters: genuine or OEM from a known brand. Don't risk an unknown filter; a poor filter can damage the engine.
• Wear parts (teeth, bushes, pins, belts, brakes): a good aftermarket part saves a lot and usually does the same job.
• Older machines or ones close to an overhaul: a good aftermarket part often makes economic sense.

How we work at MACHFIX

Every quotation clearly states the type of each part, genuine or aftermarket, and explains the price difference so you can choose. We confirm fitment with your machine's serial number before shipping.