This debate has raged for years. It depends on the part. If it’s critical to your safety, like an airbag, I’d say factory (OEM) parts only. If it’s a fender you are after, the biggest concern would be, does it fit? If an after-market fender attaches to your car the same way an original one does, and it holds a paint job, why not save a few bucks. An after-market fender will not provide any more or less protection than the original. But, if the insurance company will pay for the OEM, then why not. You won’t have the potential hassle of it not fitting your car. If you are paying for parts out of your pocket, money might be the deciding factor. This discussion deals with the stock from the factory items.
What about after-market parts that enhance the performance or look of the car? Of course, optional equipment added to an automobile after it rolls off the assembly line is not usually going to come from the factory and will only be after-market. Here’s where the insurance consumer must be careful. Insurance companies only pay for what came attached to your car from the factory. You must purchase additional coverage for upgrades you have made if you want them covered. Extra insurance for accessories, custom paint or striping, and special wheels and tires sells in increments of $1,000. Keep your receipts and take pictures of your car after every upgrade, even inside the motor. You’ll need to prove the changes if you ever have a crash or a theft claim.