Scammell started as a late-Victorian period wheelwright and coach-building business in Spitalfields, London.
The outbreak of war in 1914 presented itself as a turning point in road transport history. Mechanical transport was seen to work, proving its vast potential beyond doubt to forward thinking companies such as Scammell. George Scammell's great nephew, Lt Col Alfred Scammell was injured and invalided out of the army and he was able to apply the practical experience he had gained during the war and began developing the articulated six wheeler, which began production in 1920. This vehicle was articulated and its very low axle weight allowed it to carry 7½ ton payload at 12 mph rather than being limited to 5 mph.
In 1921, the company exhibited its first articulated vehicle, capable of carrying 7.5 tons, at the Olympia Motor Show. With the demand for this vehicle, the company first moved to a new works in Watford, and then formed Scammell Lorries Ltd in July 1922.
In 1929, Scammell designed and manufactured the "100 Tonner" low loader. Only two were produced, the first was delivered to Marston Road Services, Liverpool, for the transportation of steam engines to Liverpool docks.
Scammell were also looking for new markets, and diversified into four- and six-wheel rigid (non-articulated) designs. The 'Rigid Six-wheeler' found some success and, with its balloon tyres, at last permitted sustained high-speed long-distance road operation.
In 1934, Scammell produced the 3-wheeled 'Mechanical Horse', designed by Oliver North to replace horses in rail, postal and other delivery applications. This featured automatic carriage coupling and the single front wheel could be steered through 360 degrees. It was sold in 3- and 6-ton versions. The 3-tonner was powered by a 1,125 cc side-valve petrol engine and the 6-tonner by a 2,043 cc engine. Karrier had introduced a similar vehicle, the 'Cob', four years earlier.
From 1937, a Citroën Traction Avant -powered version was made under licence in France, by Chenard-Walcker-FAR, known as the 'Pony Mécanique'. This continued in production, in various versions, until 1970.
In the late 1940s, the 'Mechanical Horse' was superseded by the Scammell Scarab, with similar features but a much less angular cab and now with a 2,090 cc side-valve petrol engine in both models and a diesel version with a Perkins engine.
In 1967, the 'Scarab' was replaced by the 'Townsman', which had a fibre-glass cab.
The company mainly concentrated on articulated and rigid eight-wheeler lorries, from the 1920s. One vehicle not in those lines that became well-known was the six-wheeled Pioneer. This was an off-highway heavy haulage tractor first produced in 1927. It showed outstanding cross-country performance due to the design that included a sideways rocking front axle, and 2 feet (1 m) of vertical movement for each of the rear wheels.
The Scammell Pioneer was popular in the oil field and forestry (logging) markets, and formed the basis of the British Army's World War II 30-ton tank transporter. With the outbreak of war, development of new vehicles stopped and production concentrated on military Pioneers for use as artillery tractors, recovery and transporter vehicles.
Post war, foreign competition and rationalisation of the UK manufacturers led to Scammell coming under Leyland Motors Ltd in 1955. It continued production in specialist and military markets until 1988 when the site at Watford was closed and the last vehicles under the Scammell name were sold.
The Scammell Scarab was the successor to the Scammell Mechanical Horse and production began in 1948.
In the late 1920s the railway companies were looking for a suitable vehicle to use on their town parcels delivery traffic, which was predominately horse drawn. The London Midland & Scottish Railway experimented with various ideas and in late 1930 announced, jointly with Karrier Motors, a tractor unit for this purpose. The vehicle, the Karrier Cob, was powered by a twin cylinder Jowett engine and utilized a mechanism to couple existing horse trailers to the tractor unit. Meanwhile the London and North Eastern Railway had approached Napier's, the quality car and aero-engine makers for an answer to the same problem. They came up with some ideas, but did not wish to develop the concept and sold the project to Scammell Lorries of Watford. Their designer, O. D. North refined and further developed the concept of the three wheel tractor unit which automatically coupled and un-coupled trailers and in 1934 announced the introduction of the Mechanical Horse.
The Scammell Mechanical Horse, with its very 'square' wooden cab and steel chassis, remained largely unchanged until the late 1940s when the tractor section was redesigned creating the Scammell Scarab. This featured the same successful automatic coupling from the original but now used the Scammell 2,090cc side-valve engine in both the 3 ton and 6 ton versions. A diesel version was also introduced with a Perkins engine. The Scarab's cab was more rounded and made from steel and with the engine being mounted lower than in the Mechanical Horse the Scarab was much more stable. The railways for which this style of vehicle was originally designed continued to be a primary customer, although there were many other users, the manoeuvrability proving popular for companies operating in city environments.
Production of the Scarab ceased in 1967 and was replaced with the Scammell Townsman that now featured a fibreglass cab. The Townsman utilized many developments in large vehicles including vacuum-assisted hydraulic brakes and although the same automatic coupling feature was used this now used a vacuum operated release mechanism rather than a hand lever found in earlier models. Despite numerous improvements the Townsman was mainly only sold to British Rail and the Royal Mail and production ended in 1968. The Scammell or "FAR" was also made under licence by the French company Chenard-Walker and used the Citroen Traction Avant engine. Production of this version began in 1937, and was known is France as the Pony Mécanique. This continued in production, in various versions, until 1970.
A four wheel version of the Scarab was produced, although problems with the cooling system meant only around 200 were produced, the majority of which were exported to South Africa.
Scammell Lorries produced approximately 30,000 Mechanical Horses of all types; of these, about 30 original Mechanical Horses, 60 Scarabs, and 30 Townsman are known to survive together with 3 Karrier Cobs and two Jen Tugs