WW1 US Prototypes

Tracklayer Best 75

United States of America (1916)
Mock-up Training Tank – 1 Built

America was not involved in the bloody slaughter on the first years of war on the Western Front not arriving until the summer of 1917. Political pressure in the United States had very much sought to avoid becoming embroiled in the war which most Americans met on a daily basis in newspaper headlines. The US military was also fairly ill-prepared for a major European land war. When, in September 1916, a new mechanical weapon of war known as the ‘tank’ was unleashed by the British in France, it could only have served to reinforce a view of being grossly ill-prepared for a modern war.

When the first images of tanks appeared in November 1916, they were a sensation in the newspapers and newsreels of the day, capturing the public imagination. There was, of course, a serious problem in America – they did not have any. Not only did they not have any, they also did not understand the technology which was at work or have an understanding of the conditions in which a machine would have to operate. The one thing which was easy to understand was the fact of this machine being tracked and there were several American tracked vehicle manufacturers at the time.

The result was several rather hastily conceived vehicles playing ‘tank’ built around these tracked tractor chassis’ used in films, for military training, or for parades. One of the first, a rather crude box-shaped vehicle, came from C. L. Best in California in 1917 and was quickly replaced with a much sleeker vehicle with a large fully rotating turret. Rather than give the tank a direct name of its own, it simply inherited the name of the tractor on which it operated, the Tracklayer Best 75.

The Tractor

The C. L. Best Tracklayer 75 weighed in at a whopping 28,000 pounds (14 US tons / 12.7 tonnes), making it 1,500 lbs. (680 kg) heavier than the larger and more powerful 120 hp Holt tractor and 5,000 lbs. (2,268 kg) heavier than its primary competitor, the Holt 75 (23,000 lbs / 10,432 kg). Shaped in the manner of a tricycle with a single tyreless wheel at the front for steering, with a pair of track units at the back for propulsion and an engine located near the front, towards that steering wheel, the layout was common across a number of tractors of the era. It should be noted that the company founder, Clarence Leo Best, owned a patent for elements of this arrangement since 1914. Holt also owned a series of patents and accused each other of stealing their ideas. A string of litigation and acrimonious lawsuits between them followed.

The Best tractor had started life in 1912 as the C. L. Best 70 hp. Tracklayer but became the ‘75’ in 1913. Powered by a giant 4 cylinder (independently cast cylinders) ‘valve-in-head’ engine with a bore of 7 ¾” (197 mm) and stroke of 9” (229 mm) producing 40 drawbar hp at 450 rpm. The Best 75 was capable of 1.5 mph (2.4 km/h) in first gear and 2.375 mph (3.8 km/h) in second gear along with 1.625 mph (2.6 km/h) in reverse. The fluid load was 6 Imperial gallons (27.3 liters) of petrol mixed with 66 Imperial gallons (300 liters) of paraffin, 7 Imperial gallons (31.8 liters) of oil, and used 27 Imperial gallons (122.7 liters) of water for cooling.

Up until 1916, these tractors were built at the company’s plant at Elmhurst California, until manufacturing shifted to San Leandro, also in California. Production ceased in 1919 and, by the time of the merger in the early 1920s with Holt, some 734 C. L. Best Tracklayer 70 and 75 tractors had been made.

C.L. Best Tracklayer 75. Source: Haddock

In the months following the unleashing of the tank in September 1916 and even after the first photographs of it appeared in November that year, numerous imitations were created. Some were simple wooden boxes or frames covered with canvas for use as training aids or for promotional purposes. After all, what better way could there be to promote sales for tracked vehicles than a ‘tank’? The company C. L. Best managed to put together a quick ‘tank’ using one of their tractors. It was made with a large boxy-shaped body surmounted by a large fixed conning tower. The vehicle, displaying the name ‘Best 75 Tracklayer’ had worked surprisingly well for the company, appearing in some military exercises with the California National Guard, crushing down barbed wire entanglements. However, it was shockingly crude in appearance. Despite the success of the machine in the first months of 1917 or rather because of that success, C. L. Best replaced that crude body with a much sleeker and curvier body with a fully rotating turret. That second version would manage even more publicity for the tractor company, but also be used as a recruiting tool by the Army.

The original Best 75 Tracklayer ‘tank’.
Source: Crismon

The new body of the vehicle, now sporting the reorganized words to switch from ‘Best 75 Tracklayer’ to ‘Tracklayer Best 75’ on the side, was ready by April 1917. It once more took part in mock battles with the California National Guard and Coast Artillery Corps on sand dunes by a beach under the watchful eyes of onlookers.

“The monster plowed its way through all obstacles, clambering easily through dense underbrush, crashing through barbed wire entanglements and crushing wooden houses with all the startling efficiency of the British type that bewildered the Germans in France”
The Day Book, 25th April 1917

The Day Book of 25th April 1917 reported the vehicle under the skin of this leviathan as a 14-ton ‘Caterpillar’, which would make it a Holt-made vehicle, even though the vehicle was clearly sporting the name Tracklayer C.L.B. 75 on the lower parts of both sides at the front and on each side in big letters. That is because despite the vehicle looking like the more famous Holt 75 tracked tractor, it was the rival C. L. Best tracked tractor instead underneath. The weight, quoted as 14 tons, was exactly the weight of the unarmored C. L. Best Tracklayer 75, a ton heavier than the Holt 75, which no doubt added to the confusion over-identification.


The design was rather elegant in its simplicity. Looking like a giant shoe, the body was semi-circular in cross-section, with the central axis of the semicircle running longitudinally down the line of the vehicle, giving it the form of a half-cylinder. The bottom edges of this half-cylinder were attached to small outriggers from the chassis of the tractor and came to a point at the front. There, a large curved attachment was fitted, notionally for cutting wire, and bearing an uncanny resemblance to the wire cutter fitted to the Holt 75 mock-up used in the film Patria. Each half of this curved nose part of the tank was made from 4 large sections, each fastened with ‘rivets’. This is more likely to have been sheet metal over a wooden frame imitating such fixings. Small ripples and creases visible on the vehicle in some photos would indicate the shell to be made from just thin sheet metal as well. In each of these front side sections was a small semi-circular piece projecting out and pointing forwards. Each of the main sides of the vehicle was made from 9 pieces, with the first and third sections from the front also having a loophole for observation. On top of the vehicle, directly above the tracked section, was a circular turret with 8 circular openings and 12 small ovaloid ones below them. Two of the circular openings mounted the ‘guns’ at opposite ends of the turret, facing away from each other. The turret roof was a simple cone covering the whole of the top of the turret. The rear of the vehicle was angled down sharply to the frame of the tractor at the back. Two notable features which can also be seen projecting from the roofline are exhausts for the engine. Sitting in front of the turret, these would serve to produce smoke directly in front of the turret and obscured any view of the ground for the men inside.

Armor and Armament

Given that the vehicle was misidentified as Caterpillar rather than reading the actual name on the side, the claim of armor cladding made from “a lighter weight model of the armor plate used in real war” appears simple exaggeration for the reader’s benefit. The vehicle was, in fact, completely unarmored. For the size of the vehicle, any armor of value would have added several tonnes to the weight and seriously affected the albeit already low speed. Given that

The Day Book reported it weighed 14 tons and Motor Age magazine reported it at 15 tons, and that its unarmed weight was already 14 tons, clearly no protection was carried.

The same is true of the armament. The Day Book (1917) also claimed that it was fitted with a pair of “rapid fire one-pound guns … mounted in the conning tower which revolved to sweep the entire field”. Different photographs on different dates and locations confirm that this ‘conning tower’ did indeed turn, but the armament consisted of just wooden props. This is confirmed in the same article on the vehicle from The Day Book, where it says 3 men were needed in the turret to operate “the ‘one pounders’ ” – the quotation marks added to the description indicated that they were known to be fake but were to imitate real guns. The vehicle, therefore, was unarmed.

Low-quality photographs of the April 1917 exercise in which the vehicle took part, smashing a wooden house (top) and then joining in an ‘attack’ (bottom).
Source: The Day Book 25th April 1917
A clearer version of the second image from above, as seen in Bache 1917. For whatever reason, the infantry is leading the ‘attack’, with the ‘tank’ behind them on the other side of the wire. Source: Bache.


Just like the Holt 75 and other vehicles based on this type of tracked tractor, visibility was a serious problem. Even unarmored, the driver would have difficulty seeing ahead to the left due to the position of the engine blocking his view, as he was positioned approximately halfway back along the length of the track units, on the left-hand side. Confusingly, there is a cut-away drawing of the vehicle showing the driver in the turret, courtesy of Popular Science Magazine July 1917. No other crew positions are visible in that drawing, but it also curiously labels the two small features on the front, either side of the nose of the vehicle, as air intake louvers. The radiator for the tractor was indeed directly next to these areas, but it certainly would not need these two tiny louvers for air. The whole underneath of the vehicle was completely open and unarmored anyway, meaning as much air as could be needed could be drawn up from underneath. This meant that those upper features were useless for cooling air. If, of course, they were needed for air, then the logical positioning would be to turn them to face backward, so as not to direct bullets that struck them into the vehicle. In the account of the design given in ‘The Day Book’ of 25th April 1917, although it did claim the vehicle to be armored when it was not, it did give a listing for the crew. There, there is an explanation for the two features on the vehicle’s front, as it says the driver had to be assisted by a pair of lookouts at the front. With no other features from which to observe, this would mean one man stood on alongside the radiator at the front, looking out of the ‘vent’ hole and providing guidance to the driver sitting in the rear and operating more as a steersman than a true driver.

Cutaway view of the Tracklayer Best 75 showing the driver in the turret. Source: Popular Science Magazine July 1917

This would mean 3 men were required to drive the vehicle and another 3 would be sat inside the turret to operate the guns. These latter 3 persons may or may not have been able to set off small blank charges to simulate fire but, as this was done on the first version, it is likely that the second one too could ‘fire’ in this manner as well.

Tracklayer Best 75 crushing a wooden house during maneuvers in California.
Source: Zaloga
Looking more like TikTok from Return to Oz than an actual fighting machine, the Tracklayer Best 75 is still an imposing sight during this mock battle. Source: Pinterest

Image of the Tracklayer Best 75 from Literary Digest, 21st April 1917, and a wider but shorter view of the same image from Bache 1917.

Final Use

The use of this vehicle during exercises seems to have been relatively short-lived, as there was only so much such a slow vehicle could offer in the way of ‘combat’ training for the men.

However, it did not immediately disappear and was seen leading parades into at least May 1917 in California. There, displaying posters, it was used to help recruit young men and women for the war effort, as the United States had entered the war at the start of April. Its appearance in April exercises and then parades provided some reassurance to both the men being sent to fight and presumably their families, that the USA was not going to go to war without its own tanks. They would be wrong on that account, and it was not until September 1918, just two months before the war ended, that the US finally got tanks of its own into combat – notably not ones of American design. The Tracklayer Best 75 served no part in that development or process, it received no orders and presumably was quickly returned to tractor duties, with its tank-disguise removed when it was no longer needed.

Two views of the C. L. Best Tracklayer 75 from newspapers at the time. It is the same syndicated photo, but the quality varies and the background has been erased for their publication. Sources: Butte Daily Post 22/5/17 (left) and The West Virginian 4/6/17 (right)

Promotional card featuring the Tracklayer Best 75. Source: Wisconsin Historical Society
Traklayer “Best” 75 mock-up. Illustrated by Yuvnashva, funded by our Patreon campaign


Bache, R. (1917). Our Forts on Wheels. Modern Mechanix Magazine, June 1917.
Bache, R. (1917). Our Forts on Wheels. Illustrated World, June 1917.
British Pathe Video. ‘American Tanks in Action (1917).
Butte Daily Post 22nd May 1917. Big ‘Tank’ inspires youths with patriotism ambles down street through surprised traffic’
Crismon, F. (1992). US Military Tracked Vehicles. Crestline Publishing, USA
Haddock, K. (2001). Classic Caterpillar Crawlers. MBI Publishing, USA
LeGros. (1918). Traction on Bad Roads. Reprinted 2021 FWD Publishing, USA
The Day Book. (25th April 1917). Yankee Tank in Action Amazes.
The West Virginian, 4th June 1917. Big ‘tank’ inspires youths with patriotism.
US Patent US1084062 Autotractor filed 23rd June 1912, granted 13the January 1914
Wisconsin Historical Society
Young, J., Buddy, J. (1989). Endless Tracks in the Woods. Crestline Publishing, USA

4 replies on “Tracklayer Best 75”

I belive you need new category concerning all of these Amercican mock-ups. There is something wrong about sending them to prototype section.

Hi. There is another article by Andrew Hills, the “C. L. Best Tractor Tank (‘Best Tracklayer 75’)”. It seems to be the same prototype, or am I wrong?

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