OEM vs Aftermarket: Are Auto Parts Created Equal?

Being in the aftermarket auto parts business, I often find myself verbally battling with guys that are hardcore OEM auto parts only. They usually say “I only buy OEM auto parts because 'aftermarket stuff' never fits, works, lasts, etc.” They usually have an example of a part they bought from a local auto parts store that didn’t work out for them for whatever reason. Fair enough, we’ve all been there.

Now, I have absolutely no problem with OEM parts by any means. In fact, before working for 1A Auto, I was a technician at a Cadillac dealer using all OEM parts. Needless to say, I’m quite familiar with a wide range of auto parts. Do bad OEM parts exist? Absolutely! (Just ask anybody that has owned a Cadillac Catera) Do bad aftermarket auto parts exist? Absolutely! However, not all auto parts are created equal. So let’s talk about it.

"High Quality Aftermarket Auto Parts" vs. "Low Quality Aftermarket Auto Parts"

We’ll start our examples with a company that does really exist and everybody knows of them because they make absolutely fantastic suspension products. I’m leaving the name out because the auto parts that they build are more relevant than their name. For now, let’s call them “Company X”. Now, the way I understand it, about 50% of the suspension parts that Company X produces are OEM parts for brand new cars. Naturally, they also produce extras for the car dealer’s to stock in their parts departments. It would be in an OEM brand name box, but it is actually built by Company X. When the OEM’s need a part produced, Company X is given specs by the vehicle manufactures and as you may guess, they build these auto parts to the exact specifications that they are given. The OEM engineers really only need these parts to last as long as the car’s suspension warranty, without compromising safety or their own brand name in the process. All the parts function as they are designed to, but long term, some parts are better than others.

The other 50% of the auto parts that Company X produces are what I call “high quality aftermarket auto parts”. They are Company X’s aftermarket brand, built to their own specs, which are vastly improved over the OEM parts (if they need to be). They find the faults of the original designs and they correct them for their aftermarket brand because Company X wants them to last forever. Everything is greaseable (as suspension parts should be), and engineered to be better than the OEMs originally wanted. It may be a visible change in the look, or it may look identical and be internally changed. In some cases the OEM part doesn’t need to be improved upon, and the high quality aftermarket part brand is the same exact part as OEM but without the part numbers marked on them.

On the other hand, there are the cheaper options available out there which I call “low quality aftermarket auto parts”. These are typically the ones that can give “aftermarket parts” as a whole a bad name. The reason that they are the cheapest price is because they are the cheapest to produce. Being the cheapest to produce rarely equals the highest quality. The unfortunate truth to these parts is that you don’t really know if this is the part that you are buying until you attempt to attach it to your car. Before long, you need torches and welders to make it fit, and you need a new one in a few weeks.

OEM and Aftermarket Part Prices

Now you can’t talk about OEM vs. Aftermarket auto parts without talking about price. Here’s the way it works. Since the average consumer can only buy OEM parts through car dealers, the dealers can charge a premium. There is typically minimal price differences between dealers because their doesn’t need to be. They control the flow of OEM parts. Aftermarket parts are different because you can have multiple manufacturers of similar products. You can count on all of them being priced less than an OEM part from a dealer, but the quality can vary greatly. High quality aftermarket parts are priced far less than the dealer, but sold from a variety of different outlets which means competition and a super high quality part at a competitive price. Then there are the cheap (and I do mean cheap) low quality aftermarket parts. They will be priced the lowest, and may or may not be what you want when you open the box. “EEEK! What is that!?”

So although my opinion may appear to biased because of my position, I’ll give it to you anyway. I prefer the high quality aftermarket parts over OEM because I know what goes into them, and the price is right of course. Want more? Ok, fine. Recently I installed some new ignition coils in my wife’s RX8 as a general maintenance procedure. I took a few pictures for OEM vs aftermarket comparisons. The new ones were perfect in every way, and the RX8 is happier than ever. (OEM’s are on the left side of the picture, and the 1A Auto coils are on the right.)

mazda rx8 ignition oil - side viewmazda rx8 ignition oil - bottom viewmazda rx8 ignition oil - top viewmazda rx8 ignition oil - side viewmazda rx8 ignition oil - female end

So how do you tell a quality aftermarket auto part company from the others? Take a look at what else they have to offer you, including warranties and guarantees, USA based customer service, installation videos, engaging blog articles and other automotive content, etc. If it looks like they care, they probably do.


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