Bob Ditner smiled. The late-summer heat was just what the Toyota Motor Corp. engineer needed to test the new front brakes on a 2006 Lexus sedan.
For two hours he ran the Lexus on a winding, two-lane road that quickly dropped from 5,000 feet on the western rim to sea level on the valley floor. He hit the brakes more than 100 times — instruments recorded every detail — as the brake pads soared to more than 800 degrees. At that temperature, brake fluid would boil if the system wasn't properly insulated and air bubbles would form in the brake lines, making the brakes inoperable. Under those circumstances, when a driver hits the brake pedal, it "will go right to the floor and you'll keep on going," Ditner said.
Driving at 60 mph at the bottom of the slope, he slammed on the brakes. The Lexus stopped straight, true and quickly. Hot brakes may "seem like a little thing, but many drivers use their brakes constantly going downhill, and that's what we want to protect against," Ditner said.
Despite the use of increasingly realistic computer simulations, his crew was in Death Valley doing what automakers still have to do to new cars: give them road tests under the toughest conditions imaginable. In the auto trade they call it extreme testing.
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