Updated from 1:33 p.m. ESTFord Motor Company ( F) and DaimlerChrysler's ( DCX) Chrysler unit continued to have trouble selling cars in March, while General Motors ( GM) posted its second strong month in a row. Ford's U.S. car sales fell 6.6% from the year-ago period to 107,766 vehicles and are now down 11.2% year to date. Truck sales rose 8.4% to 202,799 vehicles in the month. Overall sales were 310,565, up 2.7% from a year ago. Meanwhile, GM sold 414,949 new cars and trucks in March, up 6% from a year ago. Car sales rose 9% to $179.428, while truck sales were up 4% to $235,521. "Sales momentum continued to build for GM in March, with double-digit increases at Cadillac, Chevrolet, GMC, Pontiac and Buick," the company said. In February, GM's total sales rose 6% to 353,117 from a year ago. Car sales also increased 9% to 157,011 units, while truck sales were up 4% to 196,106 vehicles. Sales in both March and February were fairly broad-based. At Ford, its F-Series truck continued to drive sales, rising 18% to 80,056 vehicles in March. The company's Jaguar and Volvo brands once again showed healthy sales gains, rising 11.2% and 5.7% respectively in March, while Land Rover sales fell 2.1% during the month. "March was a solid month and tax refunds should help keep spring sales brisk," the company said in a statement. But some economists say the yearlong rise in energy prices, which has pushed gasoline to more than $2 a gallon in part of the country, will dampen discretionary spending. In February, Ford's overall U.S. sales fell 2.4% to 261,694 vehicles from a year ago. Sales of trucks rose 4.3% to 175,884, while car sales plunged 14% to 85,810. U.S. sales at Chrysler fell 2% to 197,856 vehicles in March. Car sales dropped 10% to 40,380 vehicles, while truck sales were almost flat at 157,476. Overall sales are up 2% year to date.