The General Motors logo is seen outside its headquarters at the Renaissance Center in Detroit, Michigan in this file photograph taken August 25, 2009. U.S. automaker General Motors Co said on Wednesday it will jointly develop and assemble medium-duty commercial vehicles with truck and engine maker Navistar International Corp. The move "strengthens Chevrolet's providing commercial customers with more choices and one-stop shopping for a versatile lineup of trucks, vans and crossovers," Ed Peper, GM's U.S. vice president of fleet and commercial sales said in a statement.