ARTILLERY TRACTOR, 5-TON MODEL OF 1917.
Weights and Dimensions.
| Overall length (armored) | 133.5 in.—3,400-mm. | |
| Overall width | 63 in.—1,605-mm. | |
| Height (armored, to top of muffler) | 72.5 in.—1,845-mm. | |
| Length of ground contact | 91 in.—2,315-mm. | |
| Ground clearance | 11 in.—280-mm. | |
| Weight (complete with full equipment) | 9,200 lbs.—4,180 kg. | |
| Ground pressure (9 and 11 inch treads) | 5.6-4.5 per sq. in.—0.394-0.316 kg. per sqcm. | |
| Weight of each track | 545 lbs.—548 kg. | |
| Weight of each track shoe (9-in.) | 12 lbs.—5.45 kg. | |
| Width of track shoes | 9-11 in.—299-280-mm. | |
| Tread of tracks (center to center of tracks) | 48.875 in.—1,243-mm. | |
| Diameter of turning circle (overall clearance) | 176 in.—4,425-mm. | |
| Engine, number of cylinders | 4 | |
| Bore | 4.75 in.—220.8-mm. | |
| Stroke | 6 in.—152.5-mm. | |
| Horsepower at 1,200 revolutions per-min | 56. | |
| Oil reservoir capacity | 3.25 U. S. Gal—12.22 liters. | |
| Road speed-gear used (per hour) | ||
| Low speed at 1,200 rev. per minute of engine | 1.94 miles—3.12 kilos. | |
| Direct speed at 1,200 rev. per minute of engine | 3.92 miles—6.31 kilos. | |
| High speed at 1,200 rev. per minute of engine | 7.37 miles—11.85 kilos. | |
| Reverse speed at 1,200 rev. per minute of engine | 1.41 miles—2.27 kilos. | |
| Capacity of main gasoline tanks (two) combined | 24 U. S. Gal.—90.5 liters. | |
| Capacity of auxiliary tank under armor | 10 U. S. 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.