Video: The Problems With Aftermarket Car Parts

Editor's note: This post was originally published on January 7, 2015 and has been updated for accuracy and relevance.

When you are in a car accident, your insurance company may recommend taking your vehicle to a repair shop that uses aftermarket parts instead of original equipment manufacturer (OEM) parts. The reason for this is simple, cost. Aftermarket parts are cheaper than OEM parts, and they save the insurance company some money in the short term, while getting you back out on the road. But, there are several problems with aftermarket car parts that need to be brought to your attention, so we have put together a 3 part series that raises awareness to those problems and addresses how to correct them.

The first problem is fit. Replacing an OEM part with an aftermarket part can mean a part will be close to fitting, but won’t be perfect. When it comes to your vehicle, the term “good enough” should not be good enough. A part that does not fit perfectly won’t look right. Aesthetically, it isn’t as glaring as trying to force a square peg into a round hole, but it will leave the appearance that something is askew.

While aesthetics can be a problem, they are the least important problem that aftermarket parts can bring. The next problem is the vehicle’s performance. Depending on the part of the vehicle being replaced, any number of aspects of your vehicle’s performance can be harmed by aftermarket parts. If it’s a head lamp, as you’ll see in the video below, a part that isn’t a perfect fit could easily have connection or positioning issues. This could mean anything from a head lamp that flickers to one that doesn’t point exactly where you need it to.

On other parts of the vehicle, an improper fit can mean water getting where it is not supposed to be. This can be an inconvenience if you’re talking about a leaky trunk, or it could be much worse if you’re talking about water infiltrating the vehicle’s electrical system.

Most importantly, there is the issue of safety. Ford motors recently did a study comparing OEM parts to aftermarket parts, and what they found was that aftermarket parts were frequently made of lighter, less reliable materials. Ford Repairability Engineer Larry Coen noted, “part construction and weight and thickness comparisons revealed significant differences between aftermarket copies tested and genuine Ford structural parts. Some parts tested varied in weight by more than 50%, and Ford noted differences in the metals used to build the parts. One glaring example was in the radiator support. Ford build their radiator support out of magnesium. The aftermarket replacement was molded plastic that was pop-riveted to sheet metal.

There are two reasons why this is a safety issue. The first is impact absorption. The vehicle with the cheaper, lighter plastic and metal aftermarket parts will receive much more damage in a crash than one with heavier OEM parts. The most obvious place where this would be a factor is in the bumper reinforcements. The bumper is the first line of defense in a head-on or rear end collision. Sacrificing quality in the first line of defense means accepting greater levels of damage in an accident. The second safety issue is air bag deployment. With the radiator support Coen said, “Ford engineers consider this a critical difference because one of the vehicle’s airbag sensors is mounted to the hood latch support bracket, which is mounted to the radiator support.”

Below is a video of a car that was brought into Medine’s with an aftermarket head lamp. In the video, you will be able to see exactly how an aftermarket part can come close to fitting without being a perfect fit. Chris Medine points out flaws in the installation, and in later installments will replace the aftermarket head lamp with a proper OEM one.