Original 1986 Chevrolet Medium Duty Trucks Dealer Unit Repair Service Manual. These were what the Dealerships used to service and repair your truck. This Manual covers the repair of the Components of these Trucks. It does NOT cover the removal or installation of these Components. That was covered in a separate Shop Manual which is not included. Very informative and useful tool for the truck owner. Hard to find since they were not available to the public. Good used condition with normal wear, blemishing and soiling from use in a Dealership [see photos].