Chrysler Corp.’s parts-making unit will go solo.

Chrysler became the first major U.S. auto maker to convert its parts-making business into a wholly owned subsidiary, competing against outside sources for Chrysler business. The new company, called Acustar Inc., will not issue a public stock offering immediately but may in the future, said Acustar Chairman Robert Lutz, a Chrysler executive vice president. “Our separation from Chrysler makes it easier for us to form proprietary joint ventures to develop new technology and new product ventures,” he said.