Ford Motor Company (NYSE: F) must be asking itself when the European automotive market becomes too toxic as sales in the region slump, the euro zone teeters on the brink of disaster and carmaker predicts European losses of close to $600 million in the second quarter. REUTERS

Ford Motor Company (NYSE: F) reported U.S. July car sales were down 4 percent compared to the year before due to weak fleet sales.

Dearborn, Mich.-based Ford sold a total of 173,966 cars in the U.S. in July, down 4 percent from the previous year, despite the fact that retail sales rose 2 percent. The rise in retail sales was not enough to offset poor fleet sales which dropped 16 percent.

Consumers continued to buy Ford's fuel-efficient EcoBoost F-150 trucks, which accounted for 42 percent of overall retail sales. Ford truck sales have been particularly robust due to increased contractor demand driven by rising new housing starts during the summer. The modest gain in retail sales was attributed to overall demand for fuel-efficient cars.

Ford Motor Company (NYSE: F) shares rose 1.63 percent to $9.34 Wednesday. Ford has been relying on North American profits to offset substantial losses in Europe in 2012.