Good original 1998 Ford Truck Dealer Service/Shop Manual Supplement for the 4R100 Transmission used in Navigator, Expedition, F-150, F-250 and Econoline Van Models. It measures approx. .75" thick and contains many diagrams and illustrations along with information and service procedures unique to this Transmission. It was meant to be used in conjunction with the regular Shop Manuals for these Vehicles.Very informative and useful tool for the Ford Owner or enthusiast.