What is OEM?

When you’re buying parts and accessories for any vehicle, there tend to be a few choices you can make, and sometimes dozens. It’s true for everything ranging from door handles and brake pads to wiper blades and alternators. Some are considered aftermarket and others are called OEM.

But what’s OEM? Learn what this term means, pros and cons of OEM parts, and how the parts compare to those offered from aftermarket sources.

What is an OEM product?

The abbreviation means Original Equipment Manufacturer. At the core, it simply indicates that the parts are made to be used by the car manufacturer. For instance, a brake rotor manufactured for Honda will be branded as Honda Genuine Parts. These parts are designed and used by the specific manufacturer to be the same as the parts installed when the vehicle was brand new.

However, there are other instances to think about too. For example, Motorcraft sells Ford OEM parts, but they also sell aftermarket options under the same brand.

How do OEM products differ from aftermarket products?

Aside from dealerships, it’s less common to find parts that are truly OEM, meaning that you’ll often be paying a higher price for them. But that doesn’t mean that aftermarket parts are lower quality or bad to use – it just means they aren’t manufactured and boxed by the same company that built the parts used to assemble your car at the factory. OEM products are typically used whenever you have your vehicle serviced at a dealership.

Aftermarket products, on the other hand, are manufactured and sold by brands NOT under the OEM’s flag. For direct replacement parts, they use specs derived from the original component, so they closely resemble the OEM part. Aftermarket parts can also offer different grades like economy and premium grades, and they can also develop parts that are improved or geared toward a specific sector. For example, a truck owner might buy aftermarket shock absorbers meant for off-roading.

Advantages of OEM products

Choosing OEM parts, fluids, and accessories can have its upside. For instance:

  • They’re going to fit properly. They’re made for the same manufacturer as the original parts and to the same spec, so they’re sure to fit.
  • You know where to find them. Dealerships sell their own OEM parts.
  • The quality is always the same. You aren’t guessing if the part will be lower quality than the original.
  • They’re backed by warranty. OEMs offer a warranty on their own parts, typically for one year.

Disadvantages of OEM products

OEM provides some assurances, but it’s not always the best answer. For example:

  • Aftermarket parts may improve upon OEM flaws. An OEM part might have issues that an aftermarket manufacturer has corrected in their development.
  • There can be lower-cost parts available. One of the most prevalent obstacles to OEM parts is their high price.
  • Aftermarket parts can have better use cases. Need parts tailored to your particular needs? OEM parts are limited to one option while aftermarket parts can have dozens of options available.
  • There’s limited access to OEM parts. You’ll need to visit a dealership for your OEM parts, whereas aftermarket parts are much more readily available.

Why do manufacturers use OEM parts?

When you take your vehicle to a dealership or shop at their parts department, it’s almost guaranteed your only choice will be OEM parts. That’s because they’re made by the company they work for, and they have the market cornered for that store. There’s also some assurance of quality and consistency.

When one service department is working on the same vehicle every day, they can keep more parts on the shelf and know they’re going to sell them. That sometimes means compromising on offering options to the customer such as cheaper or better parts.

How to determine if a product is OEM or aftermarket

The easiest way to determine if a product is aftermarket or OEM is by the brand on the packaging. If the brand is the same as your car manufacturer, there’s a good chance it’s OEM. That includes brands owned by a parent company like MOPAR parts for Stellantis brands. They also tend to have a batch number and/or a serial number on the packaging too, although it depends on the part.

Aftermarket parts will often fit a wide range of makes and models, not just a single brand’s vehicles. And if you’re shopping anywhere other than the dealership, it’s a fair assumption that you’re getting an aftermarket part.

At an AutoZone near you, you’ll find aftermarket parts that fit your vehicle exactly like they should. Not sure which option is best for you? An AutoZone associate can help you narrow down the choices.

FAQ/People Also Ask

What does OEM mean?

OEM stands for Original Equipment Manufacturer, and they’re parts that are the same as the parts originally installed when your car was built, and sold under the manufacturer’s name.

What is the difference between OEM and aftermarket products?

OEM products are meant to fit a particular make and model just like original parts whereas aftermarket products might be a different grade or improved upon.

Why are OEM parts more expensive than aftermarket parts?

They’re sold by dealerships and are manufactured to precise specifications.

Are OEM parts always better than aftermarket parts?

No. Aftermarket suppliers can improve, modify, or design parts for non-factory purposes, so there are many instances where aftermarket parts are better than OEM.

Can I use aftermarket parts instead of OEM parts?

Yes, in many cases, aftermarket parts will operate like OEM parts. They can even be less expensive and/or easier to get.

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