After you're involved in a crash, your car insurance company is obligated to return your vehicle to its pre-accident condition. Unfortunately, your insurer may not want to pay for original equipment manufacturer (OEM) parts and insist on generic aftermarket parts instead.

OEM parts are manufactured by the maker of your vehicle. Non-OEM parts, often called aftermarket or generic parts, are made by third-party vendors. Many car insurance companies recommend non-OEM parts for the repair of damaged vehicles in order to keep claim costs down. The industry sees non-OEM parts as quality replacements that are a perfectly reasonable alternative to OEM parts.

A standard car insurance policy calls for repairs that use "like kind and quality" or "functionally equivalent" parts. These are commonly called aftermarket crash parts and they generally cost less than OEM parts.

You may not be aware that your car insurance coverage could allow the use of aftermarket parts. If you want replacement parts from your original car manufacturer, choose an insurance policy that guarantees OEM parts. Read your policy carefully and ask your agent before you have a claim.

For example, Chubb Personal Insurance auto coverage pays for OEM parts and GMAC Insurance has a "SmartParts Promise" guarantee of OEM parts in collision repairs that doesn't cost extra for the policyholder.

If your policy doesn't guarantee OEM parts, you have the right to request OEM parts, but you could be asked to share the repair cost.

State Farm, for example, issues repair estimates using only OEM parts for exterior crash parts, although the company may prescribe aftermarket parts for non-crash components, such as batteries and headlights. State Farm sometimes also recommends recycled crash parts, mainly for older vehicles, when it believes a recycled part will restore the vehicle to its pre-loss condition.

Progressive Casualty Insurance Co. generally recommends that non-safety related parts, such as fenders, be replaced with aftermarket parts.

"To keep the cost of insurance affordable, we write estimates using the most cost-effective solutions that will return a car to its pre-loss condition and ensure a safe, quality repair," says Leah Knapp, spokesperson for Progressive. "The decision to write an estimate that may include using a mix of OEM or non-OEM parts is based on each claim, the vehicle, the availability, type and cost of parts, etc. — all in an effort to give our customers what they tell us they want: low prices and great service."

Progressive policyholders can always request that OEM parts be used for repairs, but they may have to pay the difference between the OEM part and aftermarket part if a claims representative believes that the aftermarket part is sufficient.

A litigious issue

Past and current class action lawsuits show the tug of war that takes place over car parts.

In May 2009, a Missouri Court of Appeals reinstated a $17 million jury verdict against American Family Insurance Co. in a class action lawsuit over vehicle repairs and aftermarket auto parts (Nicholas H. Smith vs. American Family Mutual Insurance Co.). The judgment states that the plaintiffs "presented sufficient evidence for a reasonable juror to conclude that aftermarket parts are not of like kind and quality to OEM (original manufacturer parts) and that American Family breached its contracts with its policyholders when it paid to return the damaged vehicle to pre-loss condition based on the nature and cost of aftermarket parts."

A few years ago, Farmers settled a class action lawsuit (Lebrilla vs. Farmers) that alleges non-OEM parts don't meet the quality standards required by Farmers' car insurance policies. The settlement encompassed collision-repair claims made between June 15, 1996, and Nov. 1, 2006.

In settling the case, Farmers denied any wrongdoing and the company stated: "Farmers has had internal guidelines concerning the use of certain non-OEM parts such as those certified by the Certified Automobile Parts Association ('CAPA'). When Farmers specifies these parts, it does so to keep repair costs down. Through this lawsuit, it has now been brought to Farmers’ attention that a number of the parts it specified did not meet those guidelines. The court has made no determination of the quality of the parts involved in this case." Farmers agreed to pay $17 million in costs and attorney fees to the lawyers for the class.

Farmers policyholders who had claims affected by the lawsuit, which include customers of Farmers Insurance Exchange, Mid-Century Insurance Co., and other affiliates, had to file claim forms to receive $40 for each eligible hood and $20 if their crash repair required other exterior parts, such as fenders, quarter panels, tail gates and trunk lids.

What's the difference?

Aftermarket parts are certainly cheaper. According to the Insurance Information Institute (III), before generic parts existed, OEM manufacturers could sell their parts at much higher prices than they do today. The introduction of aftermarket parts forced down the price of OEM parts by an average of 30 percent, according to III. The Property Casualty Insurers Association of America estimates that use of non-OEM parts saves about $2.8 billion in insurance costs a year.

Public Citizen, a consumer-watchdog group founded by Ralph Nader, believes that non-OEM parts can be sold at reduced rates because their manufacturers do not bear the cost of research, development, advertising or special packaging. In a friend-of-the-court brief, the group stated that generic parts certified by the Certified Automotive Parts Association are equally reliable to OEM parts and that "because these CAPA parts cost less, they help maintain auto insurance rates."

The opinion that OEM parts and aftermarket parts are equally reliable is echoed by the Insurance Institute for Highway Safety (IIHS), which conducts crash tests. The organization also maintains that non-OEM parts do not degrade the safety of a vehicle repaired after a crash.

The IIHS refers to crash repair parts as "cosmetic parts." According to IIHS, the source of "cosmetic parts" is "irrelevant to safety because the cosmetic parts themselves serve no safety function. They merely cover a car like skin," with the exception of hoods, which must buckle properly during impact. But the IIHS says that "there is no evidence that hoods from aftermarket suppliers fail to perform as well as original-equipment hoods."

On the other hand, testing conducted on behalf of GM, a maker of OEM parts, claims there can be big differences between aftermarket parts and genuine OEM parts. GM conducted tests on non-OEM "certified" fenders and hoods to determine if they met GM engineering standards and specifications.

"The bottom line is that despite their 'certification,' the non-OEM hoods and fenders tested were of inferior quality and were unacceptable for GM production or service replacement parts use," wrote GM General Product Manager James K. Dalton.

Insurers are getting more savvy about holding down costs associated with OEM parts. According to CRASH Network, a news source for the collision-repair industry, State Farm has negotiated deals with original equipment manufacturers that will give State Farm a 3 percent cost break off MSRP when it buys OEM parts for use in its direct-repair "Select Service" shops.

Look before you lease

If you're leasing a vehicle, you will be required to return it in the same condition as when you first leased it. Some leasing companies will forbid you to add any parts that would reduce the vehicle's value. Under some contracts, you can't replace any parts without the leasing company's permission. If your leased vehicle needs repairs after an accident, you'll likely have to use OEM parts.

Your lease may explicitly state or imply that OEM parts must be used, but your car insurance company may not agree. In that case, your insurer will ask you to pay the difference between the aftermarket and OEM parts.

If you tell the repair shop to use aftermarket parts because you don't want to pay the difference, your leasing company may keep a chunk of your security deposit or you may be charged a disposition fee when your lease runs out.

Resale value

Consider whether you're going to trade-in or sell your vehicle before making a decision on using aftermarket parts. Dealers routinely check the crash history of a vehicle, which will reveal what kinds of parts were used in its repair. Your resale or trade-in value might be hurt if non-OEM parts are used, especially on high-end vehicles.

If you're in the market for a used car, check its crash history if you're suspicious of its condition. Carfax.com and eztitlesearch.com offer vehicle histories. Though it won't tell you if the vehicle was repaired with OEM parts, it will show if the vehicle was ever damaged in a major accident.

In a nutshell, you have the right to ask for OEM parts. Policies generally don't exclude the use of OEM parts but your insurance company may not repair vehicles with OEM parts as standard practice. You should ask. Also, a few states don't even require insurers to disclose to policyholders their use of non-OEM parts (see sidebar). It's important to know that in these states, you have to ask.