Franchised dealers of U.S. truck manufacturers sold 644,440 units in October 2002, according to data published by Ward's Communications -- 23.7% below sales for the month a year ago. The biggest drop came in Class 7 (5,038, from 8,505) and Class 3 (7,309, from 10,809). The only gains were seen in Class 8 (15,010, from 11,797) and Class 5 (2,145, from 2,001).Compared to this time a year ago, sales are down 1.2%, primarily because of declines in Class 4 (28.2%) and Class 7 (26.1%).