This blog post kind of bothers us as mechanics to write but, it’s a good question that really goes into some of the mystifying and marketing that surrounds buying new cars.
The long and the short answer really come down to no, you don’t have to use genuine parts and there’s actually an argument that you shouldn’t use genuine parts either.
While you might not believe it, vehicle manufacturers (such as VW, Toyota and Ford) actually don’t produce many of the parts for their own vehicles. Items such as spark plugs, filters, sensors and even airbags are incredibly difficult to manufacture, test and get approved which means that many of the biggest car makers in the world still outsource many components.
These parts are usually made by one of the few large automotive aftermarket brands that already exist like NGK, Bosch, Denso, Mann & Hummel and Takata.
Using aftermarket parts and only tweaking slightly for the application is a great way for the manufacturer to save money while building a car which can eventually be passed on to you as savings.
However, if these manufacturers are using Denso, NGK and Bosch for a lot of their parts already, is there any difference between these parts and the aftermarket alternative?
Well, here’s where this argument becomes a little interesting as most of these genuine parts are arguably lower quality than a lot of aftermarket variants. This is as when the manufacturer builds the car, they have to keep many of their costs in check to be able to make their money back.
While this doesn’t always directly translate to the manufacturer using low quality parts, it does mean that they’re incentivised to use cost effective parts which are then stamped with their brand name in many situations.
Aftermarket parts manufacturers are often able to look at these parts and find and fix weaknesses over a period of time. Making the aftermarket option often the higher quality part. One example of this is VW’s water pumps. These are famous for leaking and for the plastic housing failing which is why most aftermarket ones are made from metal instead.
This isn’t to say that all aftermarket parts are high quality either as there’s some real BS aftermarket parts available. But there are also some companies dedicated to high quality parts.
So do you have to or should you use genuine parts?
While many manufacturers would have you believe that it’s necessary to use genuine parts to keep your car running right (and to keep your warranty), you’ll often find that both of these points are moot.
Most warranties only require you to use ‘of genuine quality or higher’ parts (easily done by many aftermarket manufacturers). Additionally, the higher quality aftermarket parts will likely keep your car running longer anyway.
Genuine parts aren’t always a bad thing but, it’s worthwhile to find out if there’s better quality parts available to you at a more affordable prices.
This blog post was requested by Milton. If you have any suggestions for topics we should cover, reach out to us here.`