DETROIT (Reuters) - Chrysler Group LLC on Wednesday reported its third straight month of double-digit gains in the U.S. market, selling 19 percent more vehicles in September than a year ago, an indication that industry strength continued as summer waned. A Reuters survey of nine industry analysts showed expectations of a 10 percent rise to about 1.25 million vehicles sold in September industrywide. Chrysler was the first major automaker in the U.S. market to report sales. Most other automakers will release their results later Wednesday morning. Sales of Chrysler's Jeep brand shot up 47 percent, while Grand Cherokee dropped 14 percent, and Ram pickup truck sales rose 30 percent. Sales of the Chrysler brand rose 14 percent, the Dodge brand fell 9 percent and the Fiat brand rose 6 percent. Chrysler is a unit of Fiat SpA, and in mid-October is expected to debut as the merged Fiat Chrysler Automobiles on the New York Stock Exchange. (Reporting by Bernie Woodall in Detroit; Editing by Jeffrey Benkoe)