A strike against Detroit's three automakers went into its fourth day with no sign of an early breakthrough and against a threat that the walkout could soon spread. So far, the strike is limited to about 13,000 workers at three factories – General Motors, Ford and Stellantis, which includes Chrysler. The United Auto Workers union is seeking wage increases of 36 percent over four years, while the companies have offered about 20 percent. The union also is demanding a 32-hour work week for 40 hours of pay, and other changes.