Genuine vs Aftermarket Parts

When your car needs a replacement part, you are usually offered a choice you have no easy way to evaluate. Genuine or aftermarket. One sounds safer, the other sounds cheaper, and most people pick based on the price without much else to go on. It is a more interesting question than that, and the honest answer is that neither option is automatically right.

What the terms actually mean

Genuine parts are supplied by the vehicle manufacturer under their own branding. They are made to the exact specification of the component your car left the factory with.

Aftermarket parts are everything else. This is a wide category rather than a single tier of quality, and it is where the judgement is needed.

You will also see the term OEM. It sits inside the aftermarket category and it does not guarantee anything on its own. Sometimes an OEM part comes out of the same factory as the genuine one, simply without the vehicle maker's badge on the box, and you get the identical component for less. Sometimes it does not. Knowing which is which is the job.

Not all aftermarket parts are equal

This is the part that gets lost in the conversation. "Aftermarket" is not one tier of quality, it is a spectrum that runs from components matching or exceeding the original specification down to parts that will not last the year.

A quality aftermarket brand with a real engineering reputation behind it can be an excellent choice, and in some cases an improvement on the original. A no-name equivalent at a third of the price is a different proposition entirely, and the saving tends to disappear the second time you pay to have it fitted.

Knowing which is which is not something you can work out from a catalogue listing. It comes from experience.

How we decide

Our approach comes down to one rule: we will not fit a part we cannot stand behind.

We guarantee our workmanship. That guarantee is worth nothing if the component inside it fails, so the quality of the part is not a separate question from the quality of the repair. It is the same question.

In practice, that means we weigh up:

• What the part does. Safety-critical components get less latitude than a trim clip. Brakes, steering and suspension are not where we look for savings.
• What the vehicle is. Newer vehicles with more integrated electronics leave less room for a substitute that is close but not exact.
• What is available. Sometimes the same component is available without the vehicle maker's badge and the markup that goes with it. When that is genuinely the case, you get the same part for less.

Why this matters more than it used to

Modern vehicles, whatever the badge, are far more integrated than they were twenty years ago. Components are monitored by the car's electronics and expected to report back correctly, so a part that is dimensionally identical can still throw a fault code if it is not built to the right specification.

That is not a reason to default to dealership parts every time. It is a reason to be careful about which alternatives are acceptable, and to check the result rather than assume it. We have the diagnostic equipment to confirm a repair has actually resolved a fault rather than simply cleared the light.

You will always be told what is going in

Whatever we recommend, you will know what it is and why before the work starts. If there is a genuine choice between a dearer and a cheaper option, we will explain the difference in plain terms, including how long we would expect each to last, and let you make the call.

What we will not do is fit a part we are not comfortable placing our warranty on. As MTA members we are held to a required standard of service, and that warranty is part of it.

Frequently asked questions

• Are genuine parts always better? They are always fully compatible with your vehicle, which counts for something. They are not always the right choice. Sometimes genuine is the cheaper option and that is what we will use. Sometimes it costs a great deal more for no practical gain, and a good aftermarket part is the better answer. It depends on the part and the price on the day.
• Can you source genuine parts if I want them? Yes. If you would prefer genuine throughout, tell us and that is what we will fit.
• How do I know the part you used was any good? Ask. We will tell you the brand and why we chose it, and we stand behind the work either way.

Talk to us about your next repair

Matipo Garage has been repairing Christchurch vehicles since 1929, from our workshop at 16 to 18 Lowe Street, Addington. We service all makes and models, with particular experience in European vehicles.

Call 03 348 5358 or book online, and ask about a loan car if you need to keep moving while yours is with us.

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