Cold War US HMMWV Prototypes

CSVP/HMMWV Development

United States of America (1969-1985)
Development Program

The origins of the HMMWV go back to 1969 when FMC (formerly the Food Machinery and Chemical Corporation), based in California, started work on a high mobility scout car known as the XR-311.

XR-311 fitted for convoy/escort duty with .50 cal. heavy machine-gun fitted to a ring mount above the crew compartment. Source: Wheels and Tracks #4
A study by the US Army in 1972-1973 concluded that ⅔ (400,000 out of their 600,000) of their vehicles could be replaced with a single commercial light tactical vehicle without the need for good off-road performance which led to a consolidation effort in this utility class of vehicle. The outcome was the purchase of ¾ ton Dodge commercial pickup trucks which entered service as the M880 but this was still not an ideal solution to a long term problem.
By the late 1970s though, it was abundantly clear that the mish-mash of vehicles which had been in use as the Jeep was phased out of service was a hopeless situation. A new ‘Jeep’ was needed to fulfill a range of light-duty roles with good off-road mobility. The Army wanted to replace the M274 Mule, M561 Gama Goat, M792 ambulance, Dodge T125, Dodge M37, Dodge M880, Kaiser M715, and the M151 Jeep. Some preliminary work was conducted in 1974-1975 with the purpose to fill the ‘off-road’ gap in utility multi-role vehicles. At Fort Hood, the CJ-5 by Jeep, the Blazer from Chevrolet, the Ramcharger from Dodge, and the Bronco from Ford were all evaluated, but none of these vehicles were suitable.
Separately, the XR-311 was thoroughly tested by the US Military and trialed at the same time with numerous machine-guns and anti-tank weapons, such as the TOW and a 106 mm recoilless rifle. However, in a post-Vietnam defense budget era and lacking a specific requirement for such a vehicle no orders were made, although several were sold to Israel.
By 1977, Tank Automotive Command (TACOM), which in 1967 had replaced the older Ordnance Tank Command (OTAC), had seen the light and put forward the new XM966 Combat Support Vehicle Program (CSVP). The goal was to find a single vehicle to fulfill a range of combat roles, such as scouting, but most importantly, to carry the TOW ATGM, and it was estimated that about 3,800 vehicles would be needed.
Submitted bids for the XM966 CSVP were to come from AM General (who now owned all of the rights to the failed XR-311 from FMC), Chrysler, Teledyne Continental, and Cadillac Gage.
Teledyne Continental General Products Division submitted a design called the Cheetah which was actually designed by Mobility Technology International in California who were themselves a subsidiary of Chrysler. In order to produce the Cheetah though, Teledyne purchased the rights from Chrysler who were concentrating on their own submission named Saluki. Another competitor came in the form of a version of the ‘Commando’ armored car from the firm Cadillac Gage, whereas AM General initially simply submitted an improved variant of the XR-311.
By 1979, though the CVSP program was canceled by Congress which did not feel the value in spending a lot of time and money developing such a small number of vehicles and wanted a more capable platform for more roles. The requirements were changed and more rigid requirements were imposed with the release of the specifications the Army wanted to be filled. The requirements were now known as the ‘High Mobility Multipurpose Wheeled Vehicle’ of ‘HMMWV’ with an initial requirement for 50,000 vehicles.

Teledyne Continental’s HMMWV contender
The requirements for the replacement were:

  • A single vehicle family of variants from the same platform capable of satisfying joint-force requirements.
  • Excellent on and off-road performance.
  • Total vehicle weight including payload not exceeding 7,500 lbs (3,402 kg).
  • Payload of 2,500 lbs. (1,134 kg).
  • Diesel engine with an automatic transmission capable of 0 – 30 mph in 6 to 8 seconds.
  • Maximum road speed of at least 60 mph (97 km/h) and 40 mph (64 km/h) off-road.
  • Range of autonomy of 300 miles.
  • Light ballistic protection suitable to protect occupants against fragments up to 16 grams.
  • Air transportable including helicopters and C-130 aircraft and ‘droppable’ by parachute system.

An armored variant of the XR-311 submitted for trials in 1977/78. Source: Wheels and Tracks #4
TACOM required 6 categories/roles to be able to be filled by this new HMMWV:

  • Forward Observer vehicle
  • Communications vehicle
  • Utility truck
  • Ambulance
  • Weapons Carrier
  • Personnel Transport

First pattern prototype of the AM General HMMWV.
They also set the maximum limits for the dimensions of the vehicle which would ensure it could be carried by air transport craft. Because it was estimated that the vehicle would spend 40% of its time off-road, it would have to be either full-time 4 wheel drive or selective. If it was a selective 2/4 wheel drive, then a further stipulation was that it must be able to change from 2 wheel drive to 4 wheel drive while on the move rather than stop to do so. This added complication simply led makers like AM General and Chrysler to have the vehicle in 4 wheel drive permanently and only the contender from Teledyne could be switched from 2 to 4 wheel drive on the move.

Second pattern prototype AM General HMMWV during testing configured as an ambulance. Source:
As the vehicle selected would achieve very large orders for production, it is no surprise that so many firms would submit proposals to meet this requirement.
AM General submitted a revised vehicle after the 1979 HMMWV order. No longer would they be looking at the XR-311, but a newly designed vehicle based roughly on their own Jeep (SJ) vehicle. They built a prototype on a modified SJ Jeep frame and submitted it for testing at their own facility which was completed by February 1980. Five more vehicles were then built and sent to a private facility in Nevada for a 50,000 mile (80,500 km) mock trial of the tests the Army would put the design through.

Chrysler Saluki. Source:

The low silhouette of the CSVP/HMMWV is apparent in the illustration along with the relatively short cargo space at the back. A single machine gun is mounted on top with no protection for the operator or driver. Illustration by Andrei ‘Octo10’ Kirushkin, funded by our Patreon campaign.

On 8th July 1980, the project was formally approved by the Secretary of Defense and the entire HMMWV project was summed up that it “will perform the mission of all ¼ – 1 ¼ [ton] vehicles presently operating in the forward area”.
The Army released a letter of interest in July 1980 in anticipation of final specifications which came in February 1981 when TACOM once again changed the requirements for the HMMWV. They then sent the final specifications out to 61 manufacturers inviting them to bid and submit designs. Development officially began in July 1981.
The final requirements for the HMMWV (1981) were:

  • Gross vehicle weight – 3268 kg
  • Payload – 1135 kg
  • Range – 483 kg
  • Speed – 60+ mph (97+ km/h)
  • Acceleration from 0-30 mph in 6-8 seconds
  • Armor – protection from 16g fragment at 225 m/s
  • Engine – diesel
  • Maximum dimensions – 4.95m long x 2.16m wide x 1.75m high (and be be reducible)

Chrysler’s EMTV (Expanded Mobility Vehicle) under trial in 1978. Source: Wheels and Tracks #4

General Dynamics reworked version of Chryslers EMT shown with TOW ATGM and kevlar shields. Source: Wheels and Tracks #4
Five companies, American La France, FWD (Four Wheel Drive), Chrysler, AM-General (American Motors), and Teledyne Continental, submitted designs for this phase, and in April 1982 three were chosen to submit costs for the construction of 11 prototypes each for testing. These firms were Teledyne Continental ($4m), Chrysler Corporation ($4.1m), and AM General ($4m) – they were to have 11 vehicles ready before May 1982.
Those 11 prototypes would be equipped and tested in the roles of TOW missile carrier, ambulance, armament carrier, and shelter carrier although some latitude was given in terms of how to interpret these needs.
Testing of the various prototypes was broken down into phases. ‘Phase I’ was ‘Durability and Operational Testing (DT/OT)’ and began in July 1982 focussing on how well the vehicles coped with a temperate climate (tests carried out at Aberdeen Proving Grounds, Maryland) and extreme heat (tests carried out in Yuma, Arizona). Over 4,450 individual tests would be carried out to ensure each component met the stringent Army criteria including:

  • 27 checks of operator control and accessories in the crew compartment.
  • 146 checks on the engine.
  • 40 checks on the brakes.
  • 29 checks on the powertrain – from the engine to hubs.

The Durability tests were harsh – tests were to last 16 hours a day with drivers working shifts aiming to clock 20,000 miles per vehicle in the first 5 months alone.
Regarding weapons, all the prototypes examined as weapons carriers were trialed with M60 7.62 and M2 .50 cal. machine-guns and the Mk.19 40mm automatic grenade launchers. The AM General designs had brake problems during ‘Phase I’ and modifications were required before it could take part in ‘Phase II’ trials, but its parent company American Motors Corporation was in severe financial crisis and was forced to sell off AM General to LTV Aerospace and Defence for US$170 million in 1982. Another competitor, Chrysler was not faring well either and was forced to either sell off its defense arm or its car arm to stay viable. They selected to sell the defense arm known as the Defense Products Division to General Dynamics Land Systems for US$348 million in 1982, thereby selling off their entire military sector including not just the HMMWV prototype and the potential for a contract there but also its Expanded Mobility Truck (EMT) and M1 Abrams tank.
During ‘Phase II’ (automotive trials where the Army got to drive the vehicles), which started on November 1st 1982, and ‘Phase III’ (specific tactical terrain driving conditions such as rough terrain and deep wading), it was the AM General vehicle which was proven to be the most successful, but there were still problems. All told, thirty-three HMMWV prototypes were manufactured and subjected to 600,000 miles of testing on various terrain and in various environmental circumstances, not just at Aberdeen Proving Grounds (APG), but also with the US Marine Corps at Camp Pendleton and with the US Navy at the Navy Amphibious Base at Coronado, California. Tests of the HMMWVs though would later be heavily scrutinized as the Army had rushed its assessments. The original plan had been for production over 7 years, but the Army would subsequently make this just 5 years and the testing which was supposed to last 14 months was compressed into just 5. Indeed, the formal report on the testing problems had not even been finished before the production order was made which is an unusual state of affairs for a major military system.

One of the 11 prototype AM General HMMWVs seen in April 1982. Source: Wheels and Tracks #4
There were serious problems with reliability found during testing and some of these were immediately addressed, and additionally, although it was not a problem, the horizontal grille on the front was changed to a vertical grille, presumably to try and look more ‘jeep-like’. The Army had made its choice, the AM General design was to be the HMMWV they wanted, but that was not the end of the story.
It had taken years, but finally, the US Army had its ‘HMMWV’ design chosen and the contract awarded on 22nd March 1982 (GAO report states March 1983) was for the design from AM General for production over the next 5 years for over nearly 55,000 vehicles.
The official unveiling of the US Army’s new vehicle took place at the Farnborough Air Show in the UK in 1984 by US Defense Secretary Barry Goldwater.

First ‘Hummer’ rolls off the production line at Mishawaka, Indiana on the 2nd of January 1985. Source: unknown

A note on the name

The acronym HMMWV soon began to be simply called ‘Humvee’ before being shortened by AM General to just ‘Hummer’. AM General was owned by General Motors who also owned the ‘Jeep’ brand name, and having had a difficult experience in registering that brand name, they wasted no time in registering ‘Hummer’ and ‘Humvee’ as a brand name, with presumably an eye on the civilian sales marker.
In 1993, the first civilian ‘Hummers’ were sold by AM General, but soon after they sold all of their civilian marketing rights and brand name of ‘Hummer’ to General Motors who continued with it under the name ‘HUMMER’ – always in capital letters.
To further confuse the name issue there is also the ‘Heavy Hummer Variant’ or ‘HHV’ made by AM General and named by them when they still had the rights to the ‘Hummer’ name. Therefore, to be correct and to reduce confusion over the name, the military vehicle should always be referred to only as the ‘HMMWV’ or ‘Humvee’, the civilian vehicles made by AM General as ‘Hummer’ and those by GM as ‘HUMMER’.

Conclusion of development?

The AM General HMMWV had beaten the competition to win a significant contract from the military and production vehicles from the first contract were to incorporate the changes required after the conclusion of testing. It was not a cheap vehicle though, the base model HMMWV was US$20,410 and the weapons carrier versions US$28,382, meaning that the Army initially still used civilian trucks for general duties. Thus, despite having finally managed to get the all-purpose multi-role vehicle they wanted, they ended up using 70,000 civilian vehicles anyway, namely the Chevrolet Blazer to fill the M1008/M1009 Commercial Utility Cargo Vehicle (CUCV) requirement. The advantage at least was some interchangeability of engine parts between the two vehicles.
The HMMWV would go through progressive development as all vehicles do and be used for more than was originally intended. It remains an iconic military vehicle and has subsequently seen active service with numerous nations around the world although it is currently at the end of its practical user life with the US military. A whole family of vehicles based on the HMMWV has been created and the vehicle is likely to stay in service into the middle of the 21st Century.


HUMVEE, Bill Munro, 2003, Crowood Press
HMMWV Humvee 1980-2005, Steve Zaloga
TARADCOM Posture Report RCS DRCLD-101 – 1980
Hummer Humvee in Action, Jim Mesko
Wheels and Tracks No.4
GAO Report AD-A142 168 June 1984
RDI Task Final Report of Vehicle Performance Recorder, APG, May 1984
Hummer – The Next Generation, Michael Green

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2 replies on “CSVP/HMMWV Development”

One minor mistake, the article states “The AM General designs had brake problems during ‘Phase I’ and modifications were required before it could take part in ‘Phase II’ trials, but its parent company General Motors was in severe financial crisis and was forced to sell off AM General to LTV Aerospace and Defence for US$170 million in 1982”, and identifies General Motors as AM General’s parent company in 1982 but it would have been American Motors Corporation at the time. AM General was bought off of AMC in 1983 by the LTV LTV Aerospace and Defense Company and was not acquired by General Motors until some time later (From what I can see the early to mid 90s). I can see that is must have been a typo after reading the full page. Just wanted to let you guys know. I love your work and can’t wait to see your upcoming articles! 🙂

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