Chevrolet/GMC B series

The Chevrolet/GMC B series, also called the S series, was a family of cowled bus chassis built by General Motors for the 1967 to 2003 model years. It was a variant of the Chevrolet and GMC medium-duty trucks developed mainly for bus use, above all school buses, and was sold as an incomplete vehicle to second-stage body builders who made everything behind the firewall. It was first derived from the medium-duty C/K series, and later examples used the GMT530 platform and were the standard chassis for Blue Bird conventional buses. Engines included Chevrolet inline-six and V8 units and GMC V6 engines, later gasoline V8s and diesels including an 8.2 litre Detroit Diesel and a Caterpillar turbodiesel. General Motors ended production after 2002 and moved to cutaway-cab bus chassis.