NHTSA Upgrades Probe of GM Minivans

U.S. auto-safety regulators stepped up an investigation that may lead to a recall of 507,016 General Motors Corp. minivans because a rear axle part can break.

The National Highway Traffic Safety Administration inquiry involves 1997 through 1999 models of the Chevrolet Venture, Pontiac Transport and Oldsmobile Silhouette. Two crashes and 15 incidents were reported after a part called the rear-axle trailing arm broke.