Chrysler says it will close all 30 of its manufacturing plants for a month starting Friday.

The company needs to match production to slowing demand and conserve cash.

Tighter credit markets are keeping would-be buyers away from their showrooms, Chrysler says. Dealers are unable to close sales for buyers due to a lack of financing, and estimate that 20 to 25 percent of their volume has been lost due to the credit situation.

Chrysler claims it is nearing the minimum level of cash it needs to run the company and will have trouble paying bills after the first of the year.

Operations at the 30 plants will be idled at the end of shift on Friday, Dec. 19, and will not come back online until Jan. 19, 2009, or later