Ford Motor Co. could resume production of its best-selling F-150 pickups as early as May 18 at plants in Dearborn, Mich., and Kansas City, according to a source familiar with the automaker's plans.

Ford shut truck plants in Michigan, Missouri and Kentucky earlier this week because of parts shortages caused by a fire at a Michigan factory operated by a key supplier.

Ford's Louisville truck plant, which builds F-series Super Duty pickups, remains closed indefinitely.

The parts plant in Eaton Rapids, Mich., owned by Meridian Magnesium Products of America, , such as engine cradles, front-end carriers, instrument panel crossbar beams, liftgate inner structures and radiator supports.

Mercedes-Benz said Friday that SUV production at its Alabama plant stopped on Thursday because of parts shortages after the supplier fire last week.

Mercedes said it had exhausted its supply of cockpit cross-members on May 9 and did not have enough parts to resume full production. It said the Alabama plant will reopen next week on a "modified production schedule" while the automaker works with Meridian to restore parts production.

Ford executives earlier this week said the company's quarterly earnings could be affected by shutdowns at the three truck plants, but reaffirmed its full-year earnings estimate.

Ford said it was working with Chinese-owned Meridian to shift production of the affected parts to other suppliers until the fire-damaged plant can be repaired and production resumed.

The fire has also disrupted output at General Motors, Fiat Chrysler and BMW assembly plants.