Gal.—37.85 liters. Capacity of transmission case 3 U. S. Gal.—11.3 liters. Capacity of track oiler tank 2.5 U. S. Gal.—9.43 liters. Brief Description. The 5-ton artillery tractor, Model 1917, is a self-propelled road vehicle of the “Track laying” type; that is, the power is transmitted to the ground through a flexible endless chain which acts as a track and is composed of steel links and shoes cast integral and connected by hardened steelpins. The advantage of this type of tractor as compared with the usual type of wheel tractor or truck, is its ability, due to very low unit ground pressure, to negotiate very soft and uneven surfaces, impassable to the usual type of self-propelled vehicle except under the most extreme difficulties. The general design and construction of the 5-ton tractor does not differ materially from that of the modern truck except in the method of transmitting the power from the transmission unit to the ground. It is used solely as a power vehicle for hauling howitzers carriages and caissons. Each carriage and carriage limber are drawn by one tractor and each pair of caissons are drawn by one tractor. A complete description and instructions for care, maintenance, and operation are contained in the “Handbook of 5-Ton Artillery Tractor, Model of 1917.” (No. 1996). Outline Specifications. =Engine.=—Four cylinder, four cycle, valve-in-the-head type. Bore 4.74”. Stroke, 6”. Cylinder case in pairs. Horsepower 56 at 1,200 revolutions per minute. =Radiator.=—Honey-comb tubular type. Eight separate headers. =Ignition.=—Eisemann, Model G-4, high tension magneto with automatic impulse starter. =Carburetor.=—Model A Schebler carburetor with Stewart vacuum feed system; 1.5”. =Governor.=—Centrifugal flyball type mounted on special shaft and driven off camshaft gear. =Master Clutch.=—Dry plate multiple disk type. =Transmission.=—Selective sliding gear type. Three speeds forward, one reverse. Direct drive on second. Stepped up on high. =Drive.=—From transmission through bevel gears to steering clutch shaft through steering clutches to spur pinions, which mesh with intermediate spur gears, thence through outside gears, encased, to sprocket drive sleeve and drive sprockets. =Steering Clutches.=—Two used of dry plate multiple disk type. =Steering.=—By means of steering clutches operated from hand steering device and brake bands operated by foot pedals, which act on outside of steering clutch drums. =Control.=—Steering gear located on the right hand side. Change gear, master clutch operating lever, and brake lever, left of steering gear, left to right respectively. Spark and throttle levers operate on sector clamped to steering column. Steering clutch pedals right and left at bottom of, and in front of steering column. =Brakes.=—One set. External contracting type. Raybestos, or equal, lined. Operate on steering clutch housings.