Will my insurance pay for OEM parts?

Many policies cover OEM parts, especially for newer vehicles. California law requires your insurer to disclose in writing if they intend to use non-OEM parts. An OEM-certified shop will advocate with your adjuster to approve genuine parts.

Do OEM parts affect my vehicle's resale value?

Yes. Vehicles repaired with OEM parts retain higher resale value because buyers and dealers trust that safety systems and structural integrity match factory standards. Vehicle history reports can flag aftermarket structural parts.

Can aftermarket parts void my factory warranty?

Aftermarket structural parts can sometimes void manufacturer warranty coverage for the repaired area. OEM parts preserve your factory warranty and ensure safety systems remain fully supported.

Parts & Repair

OEM vs Aftermarket Parts: Why Genuine Factory Parts Protect Your Safety & Value

After a collision, your insurer may propose aftermarket parts to save money. But not all replacement parts are created equal. Understanding the difference between OEM and aftermarket auto body parts helps you protect your safety, your warranty, and your vehicle's resale value.

September 5, 20266 min readNetwork Auto Body Editorial Team

What Are OEM Parts?

OEM (Original Equipment Manufacturer) parts are the exact components your vehicle was built with at the factory. They're produced by or for the vehicle manufacturer to precise specifications, ensuring identical fit, material thickness, corrosion protection, and safety-system compatibility.

What Are Aftermarket Parts?

Aftermarket parts are third-party copies manufactured by companies other than the original automaker. Quality varies widely — some meet OEM standards, but many have thinner metal, different alloys, and inferior corrosion protection that can affect fit, crash performance, and longevity.

Fit and Finish

OEM parts are guaranteed to fit exactly because they match the factory dimensions. Aftermarket parts frequently require extra adjustment, shimming, or modifications that can leave uneven panel gaps and a less-than-perfect finish — visible signs of a previous repair that hurt resale value.

Safety and Crash Performance

Your vehicle's crumple zones, airbag timing, and ADAS (Advanced Driver Assistance Systems) are engineered around OEM structural parts. Substituting aftermarket structural components can alter how the vehicle absorbs a future impact and how sensors perform. OEM parts ensure your safety systems work exactly as designed.

Corrosion and Warranty

OEM parts carry factory corrosion warranties and are treated with the same rust inhibitors as the original. Many aftermarket parts skip or reduce these treatments, leading to premature rust. OEM parts also preserve your manufacturer's warranty — aftermarket structural parts can sometimes void coverage.

Resale Value

Buyers and dealers trust that a vehicle repaired with OEM parts retains its safety and structural integrity. Vehicle history reports can flag aftermarket structural parts, lowering offers at trade-in or sale. OEM repairs help preserve your vehicle's market value.

California Law and Your Rights

California Insurance Code §758 requires insurers to disclose in writing when they intend to use non-OEM parts. You can insist on OEM parts, especially for newer and luxury vehicles. An OEM-certified shop like Network Auto Body will document why genuine parts are necessary for safety and advocate with your adjuster.

Need Collision Repair Now?

Get a free estimate online or call any of our 5 SoCal locations. OEM parts, lifetime warranty, and direct insurance billing.

Free Estimate (818) 650-8130

Frequently Asked Questions

OEM vs Aftermarket Parts FAQs

For fit, safety, corrosion protection, warranty, and resale value, OEM parts are generally superior because they match factory specifications exactly. Aftermarket parts vary in quality and can compromise safety systems, fit, and vehicle value.