Chrysler is shutting down its Fenton North assembly plant for two weeks, starting May 23rd, because of lagging sales of the Dodge Ram Pickup trucks built there. Daimler-Chrysler says sales have been week for the Ram pickups all year. The south plant, which makes minivans, will stay open. It’s the second auto plant in the St. Louis area to have a temporary shutdown because of sluggish sales of big vehicles. Ford is closing its Hazelwood plant for a couple of weeks this month because sales of the Ford Explorer and Mercury Mountaineer SUVs are off.