"There's an awful lot of suppliers who don't know if they're going to make it through the next 30 days or not." Parts suppliers have warned that the temporary plant shutdowns by Chrysler LLC and General Motors Corp. during the U.S. automakers' Chapter 11 proceedings have thrown them into a crisis. Two suppliers have already filed for bankruptcy protection -- Visteon Corp., a top parts supplier to former parent Ford Motor Co., and Metaldyne Corp. Troy, Michigan-based Delphi, a former GM unit and the company's largest supplier, has been in bankruptcy protection since 2005 and is still struggling to emerge. News of the latest aid request bolstered auto supplier stocks Tuesday, helping many to outperform the broader market. Southfield, Michigan-based Lear Corp. led the pack, as shares jumped 37 cents, or 30.3 percent, to close at $1.59 for the day on trading volume nearly five times the daily average.