When you’re looking for a replacement part for your car, you’ve probably run across the abbreviations OEM and OES. In this article, we will go over what each designation means and help you figure out which type of part offers the best value for your money.
OEM stands for Original Equipment Manufacturer. An OEM part is usually made by a third party contract manufacturer, but it has the automaker’s brand on it. For example, GMB builds OEM water pumps for a lot of automakers. These water pumps are stamped with the automaker’s logo and packed in their branded packaging.
OES stands for Original Equipment Supplier. An OES part is made by the same manufacturer that built the OEM part found in your car. For example, if GMB built the OEM water pump in your car, GMB’s own water pump designed for your car would be an OES water pump.
OEM and OES parts are typically indistinguishable from one another when it comes to function and performance because these parts are:
OES manufacturers have the resources and equipment to build high-quality parts. Automakers deem them worthy of putting in their vehicles and putting their brand on them. It doesn’t matter whether you buy an OEM or OES part. You’d be getting the same high-quality part either way.
The best way to save money is to cut out the middleman. In this case, the automaker is the middleman. When you buy an OEM part straight from the dealer or a wholesaler, you’re paying a markup just to have the automaker’s brand on the part.
Typically, OES parts are purchased through a wholesale distributor or jobber, both of which offer low prices on quality parts. At GMB, we offer our parts through a network of wholesalers and jobbers. Check out where you can buy our OE-quality parts here.
I don’t have any brand recommendations, but here are my recent experiences with three different brands.
Back in 2012, the water pump on my father’s '03 Trailblazer EXT 5.3L started leaking out the weep hole. I replaced it with Autozone’s Duralast brand (don’t know who actually made it then, but now they may be made by Airtex). As soon as the engine got up to temp after the pump install, it started leaking where the upper hose nipple is pressed into the housing. So off it came and went back to AZ. They didn’t have another in stock, so went to another local parts store (Federated Auto Parts affiliated) and they sold me a new GMB brand pump. That pump had to be replaced last fall due to a profuse leak out the weep holes. The third pump is a new Gates. We’ll see how it goes.
Back in 2017, I helped my brother with some preventive maintenance on his then new-to-him 2004 Chevy Silverado 1500 5.3L, which included a new Gates water pump. This pump started leaking a couple months ago. Gates does have a lifetime warranty. Others might too.