How Car Testing Works

Car Testing Criteria

Testing automobiles is expensive. The automobile prototypes, or test mules, can cost several hundred thousand dollars, even for so-called economy cars. Furthermore, it requires paying the salaries of teams of engineers, paying for the costs of special measuring equipment, and shelling out for meals and accommodations for these small armies when they must conduct their experiments away from their main offices.

Therefore, an entry-level commuter car would not be subjected to the same testing criteria as a Corvette, which GM wants to market as a "world class" car. And that Corvette, likewise, would not be subjected to the same off-road rigors as a rugged Hummer.

Sometimes manufacturers get valuable design and engineering data from sources outside of their official test programs for preproduction vehicles. Some of these sources include:

  • Quality surveys by companies like J.D. Power and Associates
  • Independent media and customer reviews of existing vehicles
  • Observing trends in popular culture in how people modify their vehicles after purchase
  • Using racing innovations to make production cars faster or safer

For all their contributions to automotive advancement, test cars almost always meet an unpleasant fate. Since they're typically unfinished works that can't be sold and put under warranty, most test mules are simply sent to the crusher once their work is done. This fate was made controversially apparent in the documentary "Who Killed the Electric Car?" After General Motors decided to abandon the EV1 electric car program against the wishes of EV1 supporters, the company faced a storm of controversy as they hauled the vehicles away to be destroyed.

Ford faced similar outrage in 2004, when it decided to pull the plug on its electric car experiment with its Think model, which it had leased to customers willing to test it. A public relations nightmare for Ford ensued when word leaked that the company planned to destroy the cars after the three-year test period. The company eventually relented by agreeing to ship the cars back to Norway where they were produced [source: Associated Press].

While those particular decisions were socially and politically charged because of their environmental overtones, the fact is that test cars are routinely destroyed once manufacturers no longer need them.

For more information on how cars are tested, go to the next page.

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More Great Links


  • Brauer, Karl. "Talk Back Tuesday: Test Mules and Spy Photography." July 22, 2008. (Accessed Feb. 21, 2009)
  • Consumer Reports. "How Consumer Reports tests cars: A video guide to the methods our Auto Test Center uses to evaluate cars for Ratings and reviews." (Accessed Feb. 18, 2009)
  • Fangfang, Li. "Winter car tests thrive in Yakeshi." China Daily. Nov. 11, 2008. (Accessed Feb. 20, 2009)
  • Lutz, Bob. "At Last: Behind the Wheel of Volt Test Mule." GM FastLane Blog. June 5, 2008. (Accessed Feb. 16, 2009)
  • Nevada Automotive Test Center. (Accessed Feb. 18, 2009)
  • Paine, Chris. "Who Killed The Electric Car?" Sony Pictures Classics. 2006.
  • Pilibosian, Liz. "What's a Mule?" Cadillac Drivers' Log - Test Driving CTS All Over the World. March 26, 2007. (Accessed Feb. 16, 2009)
  • "Showing R-E-S-P-E-C-T, Ford to send Think cars to Norway." Associated Press, via USA Today. Sept. 16, 2004. (Accessed Feb. 20, 2009)
  • Weaver, Alistair. "Why the Lap Times Are a Bunch of Bull." Edmunds Inside Line. Sept. 16, 2008. (Accessed Feb. 18, 2009)
  • Woodyard, Chris. "Death Valley's a hotbed of car-testing intrigue." USA Today. Sept. 5, 2007. (Accessed Feb. 17, 2009)

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