Two years ago, Sherry Wang bought a Toyota Camry because it offered a comfortable way to commute to her job as a researcher in the Chinese city of Xian. Lately, she's been taking the bus.

"I'm afraid that my car or I will become a target" of anti-Japanese protesters, who have thronged China's streets in recent days, Wang said. "I just hope life will get back to normal as quickly as possible."

Wang illustrates why Japanese carmakers such as Toyota, Nissan and Honda are bracing for what may become a bigger crisis in China than last year's tsunami in Japan. As violent protests over control of islands claimed by both nations flare up, China's Passenger Car Association predicts Japanese brands will lose their lead over German nameplates in the country for the first time since 2005.