1971 GMC Trucks Conventional Models Series 7500 Sales Brochure. The short cab with the long count on profit. Sturdy cab construction stands up to years of strenuous service. GMC interiors work hard at relaxing. GMC chassis cut the high cost of hauling. More power to you from GMC. Chart of available Gasoline and Diesel engines. Specifications. Very good condition. ADV 71-9-(8-70)