As Saturday Night Live's Roseanne Rosanadana used to say: "It's always something." Just as auto sales heat up late in the year, automakers hit a snag in getting vehicles to dealerships. About 5,000 Teamsters strike Ryder System Inc., the nation's largest car-hauling company. Although some dealers report shortages,Corp., which relies heavily on Ryder, says its contingency plans are working out well. GM has been paying dealers $100 to drive vehicle away from distribution centers and, says a GM spokesman, it has proven successful. Customers who ordered specific vehicles might experience some delays, but dealer stocks are adequate enough to handle demand for several weeks, say manufacturers. The union says Ryder and other car haulers have violated federal laws by refusing to share economic and operations information in negotiations for a new contract. The old contract expired in May.