Aftermarket auto parts often suffer the stigma of being substandard to OEM, factory direct-parts. But does that reputation stand up to scrutiny under real-world conditions? Not always. When it comes to parts that modify and increase performance, aftermarket parts usually take the checkered flag.

The OEM (or "Original Equipment Manufacturer") label comprises any part that is produced by a vehicle's manufacturer. OEM parts are exact duplicates of components that originally came with a car or truck, which is why they are generally regarded as parts that fit well, last for years, and are worthy of the higher prices they command. After all, who better to produce parts for a specific make and model than the company that produced the vehicle itself? The latter statement is true, as far as it goes. But it fails to take into consideration a few salient, important facts. Let's take a look at them.

Many Aftermarket Parts are Produced to Standards That Meet or Exceed OEM Requirements

Aftermarket parts can be unfairly tagged as cheaply-produced "knock offs," made of substandard materials and with equally shoddy workmanship. For the majority of aftermarket components, this characterization couldn't be further from the truth. Many aftermarket manufacturers design parts to rigorous standards and test them on the very vehicles for which they're developed. And we're not just talking about laboratory testing, either; aftermarket parts are regularly installed and road-tested under strenuous road and temperature conditions.

Aftermarket Doesn't Mean Generic

Non-OEM parts are not necessarily "one size fits all" items that must be modified or customized to fit. Many of them are designed to fit individual applications and are built to fit exactly the same dimensions as their OEM counterparts. The utilization of existing hardware, such as bolts, brackets, plugs, or wiring harnesses, assures perfect fit and functionality.  

Aftermarket Parts Offer Variety in Appearance and Performance that OEM Cannot Match

Aftermarket auto parts frequently offer significant upgrades over factory parts. A xenon headlight assembly, for example, can be available in a variety of color options, all of them providing better light dispersion and wider coverage than factory-produced halogen bulbs. A performance muffler offers far more than just a throaty growl; the interior design and larger pipe diameter can produce more horsepower and better fuel efficiency than a factory muffler. A performance air filter allows for greater airflow than a standard factory filter, thus increasing horsepower and reducing fuel consumption.

Non-OEM parts frequently get a bad rap. However, evidence suggests that when shopping for replacement or performance parts, the best market is often the aftermarket.