More than seven years before General Motors Co. (GM:US) began the biggest wave of auto recalls in history, an investigator for Vanguard Car Rental USA Inc. contacted the carmaker about a fatal rollover crash in California. A driver in a new Chevrolet Cobalt rented from Vanguard’s Alamo unit lost control on a warm, dry and clear day in September 2006. Traffic had been light, according to the police report. The sedan drifted across lanes, got caught in a gravel median and rolled over. The seat belt was buckled. The air bag didn’t deploy. The driver was killed.