Intermodal rail volume rose 6.7% for the week ended Sept. 7 from the same week a year ago, the Association of American Railroads reported.
Traffic increased to 228,899 trailers and containers, AAR said in its weekly report.
Rail carload traffic rose 2.2% to 278,594 year-over-year, the rail trade group said.
Seven of the 10 carload commodity groups tracked by AAR posted increases, led by motor vehicles and parts, which jumped 21.9%. Commodities showing a decrease included farm and food products excluding grain, which fell 8.6%.
For the first 36 weeks of the year, U.S. railroads moved 8.75 million intermodal containers and trailers, up 3.6% from last year. Carload traffic dipped 1% to 10 million units.