General Motors ( GM) CEO Rick Wagoner doesn't know how to tell his own company's story, Jim Cramer said Friday on CNBC's "Stop Trading!" segment. Wagoner was interviewed earlier on the network and asked to compare his company's situation with Lehman Brothers, the investment bank that filed for bankruptcy in September. "He has far more jobs on the line than Lehman," Cramer said. "What he didn't say is the system is riddled with GM paper and with GMAC paper." Were GM to become insolvent, that could lead to a global meltdown in the trust of the U.S. system, Cramer said. "Can't let it fail," he said of GM. "It cannot fail." Also, Cramer said Fluor ( FLR) should consider acquisitions and become "the ultimate infrastructure company."