Video: Knock-off bumper part "explodes" in crash test

Consumer Reports News: August 13, 2010 11:13 AM

New crash-test video dramatically illustrates what can happen when a cheap aftermarket part suffers even a low-speed impact: It explodes into a shower of pieces.

The video, right, first shows a Ford front bumper reinforcement for a 2006-2009 Fusion in a 6.1-mph collision with a fixed barrier. The part, made of relatively pliable polycarbonate polybutylene terephthalate (PC/PBT) plastic performs as designed. It deforms as it absorbs the impact energy, then springs back into shape in the test, conducted by MGA Research, a Wisconsin-based testing firm.

Then the test is repeated with a cheaper replacement part, reverse-engineered for use on the same model, but not manufactured by Ford and bearing no brand name at all. Although the knock-off looked just like the original and had PC/PBT markings imprinted on it, materials testing revealed that it was actually made of acrylonitrile butadiene styrene (ABS) plastic, which is more brittle and not up to the job. As you can see in the video, the knock-off part failed completely on impact, breaking up into hundreds of pieces.

The difference in performance would have two consequences. “You would definitely have to replace the non-car-company part, and there’s a chance that, because it exploded, the force of the crash would have a more significant impact on the rest of vehicle, and the vehicle would experience more damage that would be more expensive to repair,” says Jack Gillis, executive director of the Certified Automotive Parts Association (CAPA), the non-profit standard-setting organization that organized the crash test.

“With the Ford part, there’s a reasonable chance that there would be relatively little damage to the vehicle,” says Gillis.

Reinforcements are only one component in modern automobile bumper systems, and their function is two-fold. In ordinary use, the bumper reinforcement gives shape and support to the attractive flexible bumper cover, which is all most people ever see of today’s bumpers. In a crash, however, the bumper reinforcement cushions the impact. Its primary purpose is to protect the vehicle, not passengers, from damage in a low-speed crash.

In higher-speed crashes, other structural parts of the bumper system do play a critical role in protecting passengers from serious injury and worse. Concerns about the safety performance of non-automaker replacement bumper parts were raised last year following a collision industry demonstration by Toby Chess, a master collision-repair instructor, who used a reciprocating saw to easily slice through a metal aftermarket bumper bar. The saw couldn’t cut the original automaker bumper bar.

Since then, some insurers have suspended use of so-called non-original equipment manufacturer (OEM) “aftermarket” bumpers in repairs. In February, CAPA, which does not yet certify the quality of bumpers, tested a sample of aftermarket bumpers and reported “serious deficiencies” in strength and metal hardness, material thickness, and fit. (See pdf.) “These deficiencies potentially place the driving public… at serious risk,” CAPA’s report said.

CAPA has taken the lead in drafting non-OEM aftermarket bumper standards, which are still in the works and are being evaluated in conjunction with the Insurance Institute for Highway Safety, an auto safety research organization that crash tests new vehicles.

Meanwhile, as we blogged last month, Ford reported that its engineers found “alarming differences” in two non-OEM aftermarket parts tested. One bumper bar was made of mild steel, instead of the ultra high-strength steel that the original Ford part uses. A radiator support was made of plastic instead of the magnesium used in the Ford part.

In computer-simulated crash tests, the imitation pieces changed the timing of the crash pulse, which might effect air-bag deployment.

“Differences in material will result in a difference in the timing of the air-bag deployment,” says Mike Warwood, Ford’s parts marketing and remanufacturing manager. “The air bag might deploy earlier than it should or later than it should. Or it might deploy when it shouldn’t or not deploy at all when it should.”

CAPA is a non-profit organization that develops standards for non-car company replacement vehicle crash parts; tests parts voluntarily submitted by aftermarket part makers; and certifies them if they pass a rigorous series of tests for materials composition, design, construction, strength, fit, finish, and compliance with any applicable federal standards. It also regularly samples production lots at the typically overseas factories to ensure continued compliance with CAPA standards.

Although factory original vehicles are carefully engineered and crash-tested to meet a complex array of federal safety standards, there are no standards for replacement crash parts—except for headlights, and CAPA tests in 2003 and 2004 found that 82 percent of 40 non-OEM lamps tested, failed to meet Federal Motor Vehicle Safety Standard 108.

The lack of standards gave rise to a thriving market for cheap copies of OEM crash parts, dating at least back to the 1980s, when collision repair shops were caught using the less-expensive knock-offs but charging auto insurers the much higher OEM price. By the mid 1980s, auto insurers realized they could benefit from this scheme and began recommending or requiring that repair shops use generic copy parts in their repairs without fully informing policy holders.

Because of complaints about the poor fit, finish, workmanship, and quality of non-automaker parts, CAPA was established in 1987 to set standards for cosmetic crash parts—hoods, fenders, trim, and other body parts, but not bumpers. Only a small percentage of non-car company crash parts are certified by CAPA. Other kinds of non-OEM replacement parts—batteries, filters, spark plugs, and shock absorbers—provide sufficient quality for their manufacturers to put their brand name on them; not so for many cheap crash parts.

–Jeff Blyskal

E-mail Newsletters

FREE e-mail Newsletters! Choose from cars, safety, health, and more!
Already signed-up?
Manage your newsletters here too.

Car Maintenance News


Cars Build & Buy Car Buying Service
Save thousands off MSRP with upfront dealer pricing information and a transparent car buying experience.

See your savings


Mobile Get Ratings on the go and compare
while you shop

Learn more