A tow truck is a truck used to move disabled, improperly parked, impounded, or otherwise indisposed motor vehicles. This may involve recovering a vehicle damaged in an accident, returning one to a drivable surface in a mishap or inclement weather, or towing or transporting one via flatbed to a repair shop or other location. A tow truck is distinct from a motor carrier that moves multiple new or used vehicles in routine transport operations; the tow truck was invented in 1916 by Ernest Holmes, Sr. of Chattanooga, Tennessee, a garage worker inspired after needing blocks and six men to pull a car out of a creek. Upon improving his design he began manufacturing them commercially; the International Towing and Recovery Hall of Fame and Museum in his home town displays restored antique wreckers, tools and pictorial histories of the industry Holmes created. Five general types of tow truck are in common usage based on the type or size of vehicle to be towed: Boom: use an adjustable boom with a winch to recover vehicles from a ditch, over an embankment, or any place the vehicle cannot be safely reach backing-up.
Some booms are fixed, some heavy pivoting A-frames. The heaviest types of boom can rotate turning the tow truck into a sort of mobile crane, called a "rotator", are reserved for heavy vehicle accidents. In the past boom trucks used a "hook and chain" system where chains are looped around the vehicle frame or axle lifted by a boom winch. A towbar with heavy rubberized mats connects the truck and vehicle, so it can be towed on its other axle. "Slings" and "belt lifts" are an evolution, with rubber straps replacing part of the chains. Slings are not used much today, but they are sometimes used for towing vehicles that have been in an accident or have one or two of the front or rear wheels missing or for pickup trucks and other vehicles that have steel bumpers. Cars equipped with all-wheel drive cannot be towed with a sling, since it can cause problems with the car's drivetrain. Wheel-Lift: evolved from the hook and chain technology to produce a large metal yoke that can be fitted under the front or rear wheels to cradle them, drawing the front or rear end of the vehicle clear of the ground by a pneumatic or hydraulic hoist so it can be towed.
This apparatus picks up the drive wheels of the vehicle touching only the tires. The wheel lift was designed by Arthur W. Nelson of Weld Built Body Co. in 1967. The name spectacle lift is common in Europe. Medium and heavy trucks use a variation, the "underlift" or "chassis lift", which lifts the axle or frame instead of the wheels. Wheel-lift trucks can have adapters which can lift the chassis. Integrated: boom and wheel-lift integrated into one unit. Used in light duty trucks to repossess vehicles or move illegally parked vehicles. Most have controls for the apparatus inside the cab of the tow truck to make quick pickup possible without the inconvenience of exiting the truck to hook up the vehicle. Heavy duty trucks are manufactured with integrated lift. Flatbed: the entire back of the truck is fitted with a bed that can be hydraulically inclined and slid back to ground level, allowing the vehicle to be placed on it under its own power or pulled on by a winch; because they carry rather than tow the vehicle, it can be immobilized.
Lift flatbed: a boom uses a wheel-lift frame to lift the vehicle vertically and load it on the bed. Used in Europe, this truck can remove vehicles; these are the most common arrangements, but are by no means exclusive, as there are flatbed units that offer a wheel-lift, boom trucks that can recover but not tow, wheel-lift units that offer a combination boom with sling. There are several sizes and weight categories of tow truck; the lightest models are based on light truck and van chassis offering boom and tow weights of around 5-to-10 tons, making them ideal for car towing. Most flatbed-type vehicles are based on medium duty and heavy duty trucks to provide the chassis strength necessary to carry entire vehicles. A step up from that are medium-duty tow trucks offering boom capacity of 15–20 tons. Heavier still are the heavy duty tow trucks based on chassis used by semi trucks, with multiple axles and the ability to tow loaded semi truck and trailer combinations, with boom capacity from 25 to 50 tons.
At the top are the rotators, which can range from 40 tons to 75 tons and come with a wealth of other features per customer specification. Tow trucks are operated by private businesses, except for major highways and toll roads, where the road authority may operate the tow trucks for that stretch of road; some police departments own tow trucks, but in the US it is common to contract police tows to private companies. Businesses who operate a large fleet of vehicles, such as school bus companies or package delivery services own one or several tow trucks for the purposes of towing their own vehicles. Government departments with large fleets may own tow truck. Police department tow trucks may be used to impound other vehicles. Heavy
An ambulance is a medically equipped vehicle which transports patients to treatment facilities, such as hospitals. In some instances, out-of-hospital medical care is provided to the patient. Ambulances are used to respond to medical emergencies by emergency medical services. For this purpose, they are equipped with flashing warning lights and sirens, they can transport paramedics and other first responders to the scene, carry equipment for administering emergency care and transport patients to hospital or other definitive care. Most ambulances use a design based on pick-up trucks. Others take the form of motorcycles, buses and boats. Vehicles count as an ambulance if they can transport patients. However, it varies by jurisdiction as to whether a non-emergency patient transport vehicle is counted as an ambulance; these vehicles are not equipped with life-support equipment, are crewed by staff with fewer qualifications than the crew of emergency ambulances. Conversely, EMS agencies may have emergency response vehicles that cannot transport patients.
These are known by names such as fly-cars or response vehicles. The term ambulance comes from the Latin word "ambulare" as meaning "to walk or move about", a reference to early medical care where patients were moved by lifting or wheeling; the word meant a moving hospital, which follows an army in its movements. Ambulances were first used for emergency transport in 1487 by the Spanish forces during the siege of Málaga by the Catholic Monarchs against the Emirate of Granada. During the American Civil War vehicles for conveying the wounded off the field of battle were called ambulance wagons. Field hospitals were still called ambulances during the Franco-Prussian War of 1870 and in the Serbo-Turkish war of 1876 though the wagons were first referred to as ambulances about 1854 during the Crimean War; the history of the ambulance begins in ancient times, with the use of carts to transport incurable patients by force. Ambulances were first used for emergency transport in 1487 by the Spanish, civilian variants were put into operation during the 1830s.
Advances in technology throughout the 19th and 20th centuries led to the modern self-powered ambulances. Ambulances can be grouped into types depending on whether or not they transport patients, under what conditions. In some cases, ambulances may fulfil more than one function (such as combining emergency ambulance care with patient transport Emergency ambulance – The most common type of ambulance, which provide care to patients with an acute illness or injury; these can be road-going vans, helicopters, fixed-wing aircraft or converted vehicles such as golf carts. Patient transport ambulance – A vehicle, which has the job of transporting patients to, from or between places of medical treatment, such as hospital or dialysis center, for non-urgent care; these can be buses or other vehicles. Response vehicle – Also known as a fly-car, nontransporting EMS vehicle and variations. A vehicle, used to reach an acutely ill patient and provide on scene care. In some places, these vehicles can transport a patient, but only if they are able to sit in a regular car seat.
Response units may be backed up by an emergency ambulance which can transport the patient, or may deal with the problem on scene, with no requirement for a transport ambulance. These can be a wide variety of vehicles, from standard cars, to modified vans, pedal cycles, quad bikes or horses. Fire engines are used for this purpose in North America; these units can function as a vehicle for supervisors. Charity ambulance – A special type of patient transport ambulance is provided by a charity for the purpose of taking sick children or adults on trips or vacations away from hospitals, hospices or care homes where they are in long term care. Examples include; these are based on a bus. Bariatric ambulance – A special type of patient transport ambulance designed for obese patients equipped with the appropriate tools to move and manage these patients. In the US, there are four types of ambulances. There are Type I, Type II, Type III and Type IV. Type I is based upon a heavy truck chassis and is used for Advanced Life Support and rescue work.
Type II is a van based ambulance with few modifications except for a raised roof and is used for basic life support and transfer of patients. Type III is a van chassis but with a custom-made rear compartment and has the same uses as Type I ambulances. Type IV is for smaller ad hoc patient transfer that use smaller utility vehicles in which passenger vehicles and trucks would have difficulty in traversing, such as large industrial complexes, commercial venues, special events with large crowds. Ambulances can be based on many types of vehicle although emergency and disaster conditions may lead to other vehicles serving as makeshift ambulances: Van or pickup truck – A typical general-purpose ambulance is based on either the chassis of a van or a light-duty truck; this chassis is modified to the designs and specifications of the purchaser. Vans may either retain their original body and be upfitted inside, or may be based on a chassis without the original body with a modular box body fitted instead.
Those based on pickup trucks always have modular bodies. Those vehicles intended for intensive care or require a large amount of equipment to be carried may be based on
Four-wheel drive called 4×4 or 4WD, refers to a two-axled vehicle drivetrain capable of providing torque to all of its wheels simultaneously. It may be full-time or on-demand, is linked via a transfer case providing an additional output drive-shaft and, in many instances, additional gear ranges. A four-wheeled vehicle with torque supplied to both axles is described as "all-wheel drive". However, "four-wheel drive" refers to a set of specific components and functions, intended off-road application, which complies with modern use of the terminology. 4WD systems were used in many different vehicle platforms. There is no universally accepted set of terminology to describe the various architectures and functions; the terms used by various manufacturers reflect marketing rather than engineering considerations or significant technical differences between systems. SAE International's standard J1952 recommends only the term All-Wheel-Drive with additional sub classifications which cover all types of AWD/4WD/4x4 systems found on production vehicles.
Four-by-four or 4x4 is used to refer to a class of vehicles in general. Syntactically, the first figure indicates the total number of wheels, the second indicates the number that are powered. So 4x2 means a four-wheel vehicle that transmits engine torque to only two axle-ends: the front two in front-wheel drive or the rear two in rear-wheel drive. A 6×4 vehicle has three axles, two of which provide torque to two axle ends each. If this vehicle were a truck with dual rear wheels on two rear axles, so having ten wheels, its configuration would still be formulated as 6x4. During World War II, the U. S. military would use spaces and a capital'X' – like "4 X 2" or "6 X 4". Four-wheel drive refers to vehicles with two axles providing torque to four axle ends. In the North American market the term refers to a system, optimized for off-road driving conditions; the term "4WD" is designated for vehicles equipped with a transfer case which switches between 2WD and 4WD operating modes, either manually or automatically.
All-wheel drive was synonymous with "four-wheel drive" on four-wheeled vehicles, six-wheel drive on 6×6s, so on, being used in that fashion at least as early as the 1920s. Today in North America the term is applied to both heavy vehicles as well as light passenger vehicles; when referring to heavy vehicles the term is applied to mean "permanent multiple-wheel drive" on 2×2, 4×4, 6×6 or 8×8 drive train systems that include a differential between the front and rear drive shafts. This is coupled with some sort of anti-slip technology hydraulic-based, that allows differentials to spin at different speeds but still be capable of transferring torque from a wheel with poor traction to one with better. Typical AWD systems are not intended for more extreme off-road use; when used to describe AWD systems in light passenger vehicles, it refers to a system that applies torque to all four wheels and/or is targeted at improving on-road traction and performance, rather than for off-road applications. Some all-wheel drive electric vehicles solve this challenge using one motor for each axle, thereby eliminating a mechanical differential between the front and rear axles.
An example of this is the dual motor variant of the Tesla Model S, which on a millisecond scale can control the torque distribution electronically between its two motors. Individual-wheel drive is used to describe electric vehicles with each wheel being driven by its own electric motor; this system has inherent characteristics that would be attributed to four-wheel drive systems like the distribution of the available torque to the wheels. However, because of the inherent characteristics of electric motors, torque can be negative, as seen in the Rimac Concept One and SLS AMG Electric; this can have drastic effects, as in better handling in tight corners. The term IWD can refer to a vehicle with any number of wheels. For example, the Mars rovers are 6-wheel IWD. Per the SAE International standard J1952, AWD is the preferred term for all the systems described above; the standard subdivides AWD systems into three categories. Part-Time AWD systems require driver intervention to couple and decouple the secondary axle from the driven axle and these systems do not have a center differential.
The definition notes. Full-Time AWD systems drive both rear axles at all times via a center differential; the torque split of that differential may be fixed or variable depending on the type of center differential. This system can be used on any surface at any speed; the definition does not address exclusion of a low range gear. On-Demand AWD systems drive the secondary axle via an active or passive coupling device or "by an independently powered drive system"; the standard notes that in some cases the secondary drive system may provide the primary vehicle propulsion. An example is a hybrid AWD vehicle where the primary axle is driven by an internal combustion engine and secondary axle is driven by an electric motor; when the internal combustion engine is shut off the secondary, electrically driven axle is the only driven axle. On-demand systems function with only one powered axle until torque is required by the second axle. At that point either a passive or active coupling sends torque to the secondary axle.
In addition to the above primary classifications the J1952 standard notes seconda
Cab-over known as cab over engine, cab forward, or forward control, is a body style of truck, bus, or van that has a vertical front, "flat face" or a semi-hood, with the cab of the truck sitting above the front axle. This contrasts with a conventional truck; this truck configuration is common among European and Asian truck manufacturers. European regulations set restrictions for both the total length and the length of the load area, which allow a cab length of 2.35m in combination with the maximum load area length. This allows a sleeper cab with a narrow bunk, would allow a bonneted day cab. Nonetheless, no manufacturer in Europe produces such day cabs with bonnets; the last manufacturer of a conventional in Europe, stopped production in 2005. Speaking, Asian regulations are stricter, the shorter journey distances allow more heavy trucks to forego sleepers to save more length. Cabover trucks are used in the United States for refuse collection, terminal tractors, other vocational applications requiring a tight turning radius or frequent ingress/egress by the driver.
Autocar, the oldest surviving motor vehicle manufacturer in America, produces only cabover trucks. Although cabover trucks were popular among United States heavy truckers and trucking companies during the 1970s because of strict length laws in many states, when those length laws were repealed, most heavy-truck makers moved to other body styles. One of the reasons is the Federal Bridge Formula, unique to the USA, encourages spreading out the load. If axle distances are too tight, the maximum load allowance is reduced. For COEs operated at maximum weight in the USA, this required an axle directly behind the front bumper; this cab design caused an awkward climb into the cab for the driver, forcing them to climb up behind the front wheel moving to the front and into the cab. European or Chinese or Japanese truckers enter their cab in a straight fashion with handrails left and right. Cabovers are very popular in the USA's light- and medium-duty truck segment where compact size is required for urban mobility without sacrificing payload.
American companies Paccar and Freightliner still manufacture traditional cab over engine designs for the Australian and South African markets where length restrictions still make them advantageous. In Australia both American and European/Japanese/Chinese types, as well as the conventional type are common. Cab over engine types dominate urban and light duty use, with conventional trucks predominating in remote and off-road areas. Both types are common for highway use; the first truck in the United States was built by Autocar in 1899 using a format called "engine-under-the-seat" and was available with optional 5 or 8 horsepower motors. Although early Autocar trucks were not "cab-over", since the truck did not have a cab, per se, they were the fore-runners to COEs; the Sternberg company of Wisconsin produced cab-over trucks as early as 1907, though by 1914 only their seven-ton model was a cab-over. They reintroduced the cab-over layout in 1933 with their "Camel Back" model, which allowed the cab to be tilted to access the engine.
The introduction of the first modern cab-over layout in the United States is credited to industrial designer Viktor Schreckengost, with engineer Ray Spiller, designed a cab-over truck for the White Motor Company in 1932. Schreckengost was joined by other designers such as Raymond Loewy who designed the Metro series of vans and trucks for International Harvester; the bodies for these vehicles were produced by the Metropolitan Body Company. The company produced a wide variety of truck and commercial bodies for several vehicle manufacturers such as Chevrolet, Dodge Bros. and International Harvester until 1948 when they were purchased by the latter. MBC was instrumental in the development of COE route delivery bodies in the 1930s; the laws of the time limited overall truck length to 42 feet on highways. Setting the cab over the engine and front axle shaved several feet off the length of the tractor, feet which could be added to the length of the trailer while keeping the dimensions of the entire truck within the permissible limit.
Schreckengost patented the design in 1934. Autocar reintroduced the engine-under-the-seat format with their Model U in 1933, which became a staple of U. S. roads and the U. S. military through World War II and well into the 1950s. White-Freightliner introduced its first tilting cab-over design in 1958, which allowed the entire cab to tilt forward for access to the engine. In Class 8 tractors, the cab-over design allows the vehicle's wheelbase to be shorter than in the conventional arrangement, wherein the engine is placed in front of the cab, covered by a horizontal or sloping hood that opens to allow engine access, its shorter wheelbase allows cab-over semi trucks to have a shorter overall length, thereby allowing for longer trailers to be used. For light- and medium-duty solid- or rigid-axle trucks, the cab-over design requires less length for the cab and engine, in a given wheelbase, therefore allows a greater length for the truck body or load area. In both class 8 tractors and light- and medium-duty vocational trucks, the cab-over-engine design gives the COE model an advantage in maneuverability over a conventional model.
And since COEs are generally
Willys Hurricane engine
The Willys F4-134 Hurricane was an inline-4 piston engine and powered the famous Jeep CJ in the CJ-3B, CJ-5, CJ-6 models. It was used in the Willys 473 and 475 pickups and sedan deliveries, it replaced the Willys Go Devil engine, used in the MB Jeep and other early Jeep-based models like the Jeepster. This engine was built by Mitsubishi for their license-built Jeep, as well as other applications; the Hurricane was based on the earlier Go-Devil flathead engine. To get more power from the engine, the induction system was changed from the Go-Devil's side-valve configuration to an inlet-over-exhaust configuration, or "F-head"; this allowed the valves to be larger and the combustion chamber to be smaller, improving flow and increasing the compression ratio. The compression ratio rose from 6.5:1 in the Go-Devil engine to 7.5:1 in the Hurricane engine, although a version of the Hurricane engine was made with a 6.9:1 compression ratio. The L134 Go Devil was updated with the F-head to become the F134 in 1950.
This engine produced a gross output of 75 hp at 4000 rpm and 114 lb⋅ft of torque at 2000 rpm with a 7.5:1 compression ratio. The gross power and torque outputs fell to 72 hp and 112 lb⋅ft when the engine had a 6.9:1 compression ratio. Bore and stroke dimensions were the same as the L-head engine at 3 1⁄8" x 4 3⁄8" giving 134.2 cu in. The F4-134 was introduced in 1950 in the Jeep Truck. Vehicles with this engine were given the model designation 4-73; this engine was not placed in a CJ until the introduction of the CJ-3B in 1953, which had a distinctive high hood to accommodate the much taller engine. The engine remained in production until 1971, after American Motors Corporation purchased Kaiser Jeep. Applications: 1950–1961 Willys Jeep Truck 1950–1961 Willys Jeep Wagon 1950 Willys-Overland Jeepster 1952–1971 Willys M38A1 1953 Willys 475A Lark 1953–1968 Willys CJ-3B 1955–1971 CJ-5 1956–1971 CJ-6 1965-1967 DJ-5 1966–1971 Jeepster Commando The F6-161 Hurricane is an F-head version of the L6-161 Lightning flathead straight six.
It was used in the Model 685 Station Wagon. BF-161 The BF-161 has a 3 1⁄8 inch bore and a 3 1⁄2 inch stroke, a one-barrel carburetor, an output of 90 hp at 4400 rpm and 135 lb⋅ft of torque at 2000 rpm, its 161.1 cu in displacement features a compression ratio of 7.6:1.2600 The 2600 was the same BF-161 engine made in Brazil by Willys-Overland's subsidiary, but it had two one-barrel carburetors and had an output of 130 hp at 4400 rpm and 140 lb⋅ft of torque at 2000 rpm. The compression ratio remained 7.6:1.3000 The 3-liter version is identical to the BF-161 engine with the stroke increased to 4 inches giving it a displacement of 3,016.5 cc. With a 2-barrel carburetor it produced 140 hp at 161 lb ⋅ ft of torque at 2000 rpm, it had a higher compression ratio of 8:1. It used a different head with removable intake manifold. After Ford acquired Willys-Overland do Brasil, they reverted the engine to its former head design with integral intake manifold, improved cooling between cylinders 5 and 6 and installed a side-mounted oil filter, instead of the front-mounted, hose connected arrangement used by Willys.
Applications: 1961–1962 Willys Aero 1963–1971 Willys Aero 2600 1960-1974 Willys-Overland Jeep and Rural Willys 1968–1971 Willys Itamaraty 3000 1972-1974 Ford Maverick six-cylinder version in Brazil The 6-226 "Super Hurricane" was a L-head 6-cylinder from Continental with a bore of 3 5⁄16 inches and stroke of 4 3⁄8 inches, giving a displacement of 226.2 cu in. Horsepower rating is 105 hp at 3600 rpm or 115 hp at 3650 rpm, as well as a torque rating of 190 lb⋅ft at 1400 rpm or at 1800 rpm, depending on the year of production. Mitsubishi built a version of the Hurricane from 1954 as the JH4 for use in their license-built version of the Jeep, they developed a 61 PS overhead-valve diesel version of the same, called KE31. This was turned into a 3.3 liter six-cylinder version with the same internal dimensions, producing 85 PS, named KE36. These diesel engines were used in the Jeep, but in a number of light to medium-weight trucks and buses
Willys was a brand name used by Willys–Overland Motors, an American automobile company best known for its design and production of military Jeeps and civilian versions during the 20th century. In 1908, John Willys bought the Overland Automotive Division of Standard Wheel Company and in 1912 renamed it Willys–Overland Motor Company. From 1912 to 1918, Willys was the second-largest producer of automobiles in the United States after Ford Motor Company. In 1913, Willys acquired a license to build the Charles Knight's sleeve-valve engine which it used in cars bearing the Willys–Knight nameplate. In the mid-1920s, Willys acquired the F. B. Stearns Company of Cleveland and assumed continued production of the Stearns-Knight luxury car, as well. John Willys acquired the Electric Auto-Lite Company in 1914 and in 1917 formed the Willys Corporation to act as his holding company. In 1916, it acquired the Russell Motor Car Company of Toronto, Ontario, by 1917, New Process Gear, in 1919 acquired the Duesenberg Motors Company plant in Elizabeth, New Jersey.
The New Jersey plant was replaced by a new, larger facility in Indianapolis, was to be the site of production for a new Willys Six at an adjacent site, but the depression of 1920–21 brought the Willys Corporation to its knees. The bankers hired Walter P. Chrysler to sort out the mess and the first model to go was the Willys Six, deemed an engineering disaster. Chrysler had three auto engineers: Owen Skelton, Carl Breer, Fred Zeder begin work on a new car referred to as the Chrysler Six. To raise cash needed to pay off debts, many of the Willys Corporation assets were put on the auction block; the Elizabeth plant and the Chrysler Six prototype were sold to William C. Durant in the process of building a new, third empire; the plant built Durant's low-priced Star, while the Chrysler Six prototype was reworked to become the 1923 Flint. Walter Chrysler and the three engineers, working on the Chrysler Six all moved on to Maxwell-Chalmers where they continued their work launching the six-cylinder Chrysler in January 1924.
In 1926, Willys–Overland introduced a new line of small cars named Willys–Overland Whippet. In the economic depression of the 1930s, a number of Willys automotive brands faltered. Stearns-Knight was liquidated in 1929. Whippet production ended in 1931. Production of the Willys-Knight ended in 1933. In 1932, Ward M. Canaday, who beginning in 1916 had done advertising for the company before becoming a full-time employee, had taken on the role of chairman, he helped guide the company through its current receivership. At this time, Willys decided to clear the boards and produce two new models – the 4-cylinder Willys 77 and the 6-cylinder Willys 99 – but since the firm was once again on the verge of bankruptcy, only the 77 went into production, it was forced to sell its Canadian subsidiary, itself in weak financial shape, started a massive reorganization. Only the main assembly plant and some smaller factories remained the property of Willys–Overland; the other assets were sold off to a new holding company that leased some of the properties back to W-O.
The parent company was thus able to ride out the storm. In 1936, the Willys–Overland Motor Company was reorganized as Willys–Overland Motors. In 1937, Willys redesigned the 4-cylinder model, it gained a semistreamlined body with a slanted windshield, headlamps integrally embedded into the fenders, a one-piece, rounded hood transversely hinged at the rear. For 1939, the Model 39 featured Lockheed hydraulic brakes, a two-inch increase in wheelbase to 102 inches and an improved 134 DID four-cylinder engine with power increased from 48 to 61 hp; the Model 39 was marketed as an Overland and as a Willys–Overland rather than as a Willys. In 1929, the company built a factory that built vehicles located at what is now 6201 Randolph Street, Commerce City, California. During the war, the factory built aircraft assemblies for Hudson Bombers; when the war ended, the factory resumed automobile production and was one of two locations to build the first CJ2A, as well as the Willys Aero. The factory was closed in 1954.
The location is now occupied by Prologis Eaves Distribution Center. Willys–Overland was one of several bidders when the War Department sought an automaker that could begin rapid production of a lightweight truck based on a design by American Bantam. In 1938, Joseph W. Frazer had joined Willys from Chrysler as chief executive, he saw a need to improve the firm's 4-cylinder engine to handle the abuse to which the Jeep would be subjected. This objective was brilliantly achieved by ex-Studebaker chief engineer Delmar "Barney" Roos, who wantedan engine that could develop 15 horsepower at 4,400 r.p.m. and run for 150 hours without failure. What he started with was an engine that developed 48 horsepower at 3,400 r.p.m. and could run continuously for only two to four hours... It took Barney Roos two years to perfect his engine, by a whole complex of revisions that included closer tolerances, tougher alloys, aluminum pistons, a flywheel reduced in weight from fifty-seven to thirty-one pounds. Production of the Willys MB, better known as Jeep, began in 1941, shared between Willys and American Bantam.
8,598 units were produced that year and 359,851 units before the end of World War II. Willys–Overland ranked 48th among United States corporations in the value of World War II military production contracts. In total, 653,568 military Jeeps were manufactured; the origin of the name "Jeep" has been debated for many years. Some people believe "Jeep" is a phonetic pronunciation of the abbreviation GP, from "General Purpose", used as part of the of