Ford Motor Co. said it would cut smog-forming emissions starting this fall on its entire North American pickup truck line, a move that makes it the only major automaker to convert most of its light truck fleet into low emission vehicles (LEV). The announcement follows a similar one from Ford 18 months ago when the world's No. 2 automaker said it would turn its one million or so sport utility vehicles and Windstar minivans into LEVs, which meet California's more-stringent air-quality requirements.