BMW posted its best March sales ever, helping the automaker shrink Mercedes-Benz's 2014 lead. BMW sold 19 percent more vehicles last month than the previous year, led by its mid-size sedans and SUVs, while Mercedes had a gain of only 11 percent in March from a year earlier. BMW sold just over 32,000 cars in March compared to Mercedes' 27,500. This puts Mercedes lead over BMW at just 237 vehicles. The race to become the top luxury auto maker continues.