OE – Original Equipment – This part is made by the auto manufacturer or an auto parts supplier and is marked with the auto manufacturer’s logo and/or on the auto manufacturer’s box.
OEM Original Equipment Manufacturing
Original Equipment Supplier OES
Automakers don’t make all the parts they put into their vehicles during assembly or repair, they contract with autoparts manufacturers to make parts for them. For the most part, the automaker makes the body, frame, and major engine components; the rest are ‘contracted’ to OEM/OES manufacturers. The automaker provides the specifications to the OEM/OES manufacturers for the parts they need. The OEM/OES builds the part to these specifications, adds a logo, and ships it to the automaker.
Bosch, Bilstien, Boge, Beru, Mann, ATE to name a few are all OEM or OES suppliers to car manufacturers. They make parts from spark plugs to exhaust parts. The difference between OE and OEM/OES is mainly that the OEM/OES usually do not have the car manufacturer’s logo, but they are exactly the same part. Sometimes the OEM/OES company removes the logo from the part so as not to affect the contract with the car manufacturer. The same part that comes off the same assembly line as the OE part.
OEM/OES parts are less expensive because they don’t go through the automaker’s parts system. Every time an OE part passes through a depot, warehouse, or dealer, a little more money is added to the cost of the part. This is the main reason that original equipment parts cost more. OEM/OES do not go through this procedure, our buyers get them directly from the manufacturers, keeping prices low.
Aftermarket – Aftermarket parts are just that, aftermarket. They are not made by car manufacturers. They may be made by one of the original equipment manufacturing companies or by a completely different manufacturer. The main difference is that they are not built entirely to the car’s manufacturing specifications. This is not always bad. An example is Bilstien. They are an OEM/OES supplier, but also offer aftermarket parts. There are HD struts/shocks that are OE, but their sport struts/shocks and suspension kits are not made to OE specs, better but not OE, so it’s now an aftermarket part. Another example is the Stewart EMP BMW water pumps. Stewart EMP is NOT an OEM/OES manufacturer, but the pump they make is better and stronger than the OE. It’s an aftermarket part, but a better part overall.
But yet another example of a BAD aftermarket part is a counterfeit part. Counterfeit part manufacturers use reverse engineering to obtain part specifications without paying the automaker. And almost all the time these parts are made with very low quality components. Sometimes these pieces are very difficult to identify because so much emphasis is placed on the appearance of the piece and not the material it is made from. One way to identify a counterfeit part is its incredibly low price, the old adage that you get what you pay for fits here. The best way to avoid these cheap, low-quality parts is to buy your parts from a reputable source, one that offers a warranty and return policy.
Almost all performance parts are aftermarket parts, again be careful with these parts as well. Buy from a trusted supplier or manufacturer.
