Ford Motor Co.’s August sales were sluggish, prompting analysts to lower domestic vehicle sales to an annualized 13.3 million from the 13.7 million forecast made Wednesday when analysts had only Chrysler Corp. and General Motors Corp. data on hand.

Ford reported August light truck sales at 161,549, down 4.4 percent from last year, with car sales at 134,110, down 6.8 percent from 1995 levels.

“I’m a little surprised at the slow truck sales, which we expected to be flat,” said Maryann Keller, economist with Furman Selz. “Ford’s recent pattern has been weak on car sales, so those figures are not a surprise.”