The Humvee is a 4×4 car/light truck hybrid designed to do many jobs. It’s built to transport cargo, people, or gear, carry tubes with missiles, fight fires, and serve as a command and control vehicle.
It has become the symbol of half a dozen US military interventions and is instantly recognizable worldwide. But is it the best choice for today’s war zones? Click the Street Legal Humvee For Sale to learn more.
For over 40 years, the High Mobility Multipurpose Wheeled Vehicle, commonly known as the Humvee, has served all branches of the United States Armed Forces. It is also a staple in many military operations around the world. The Humvee is the quintessential symbol of America’s power.
It all began in 1979 when the Army started drafting the specifications for a new tactical vehicle to replace its M151 MUTT and CUCV 4×4 light utility fleets and the 6×6 Gama Goat. Three companies were awarded contracts to design prototypes for testing: AM General, Chrysler Defense and Teledyne Continental. Each of the three vehicles had to meet certain requirements, such as being able to climb a 60 percent grade or traverse a 40 percent slope and be capable of fording 2.5 feet of water without a snorkel or 5 feet with one.
The HMMWV, as it came to be known, was developed to be an all-purpose workhorse, serving as a cargo carrier, troop transport vehicle and command center on the battlefield. These four-wheeled vehicles became especially prominent after the Gulf War in 1991 and their rocky terrain-navigation abilities were showcased worldwide. Soon, civilian versions of the vehicle were on the market and even President Bill Clinton and Arnold Schwarzenegger owned them (before the latter became governor of California and champion of emissions standards).
The HMMWV was later replaced by the Mine-Resistant Ambush Protected (MRAP) vehicles that are still in service today. These vehicles are heavily armored and have a hull that deflects mine blasts up and away from the vehicle. While the MRAP has a few advantages over the Humvee, such as better passenger protection, it is not a full replacement. In the future, the military hopes to replace the Humvee completely with a more modern vehicle called the Joint Light Tactical Vehicle, or JLTV.
Design
As the military evolved from World War II to the era of guerrilla warfare, the quarter-ton M151 Jeep was no longer enough. By 1979, the Army issued a request for proposal to design a new vehicle that could carry more people and gear on off-road terrain and over long distances. AM General and Chrysler Defense received contracts to create prototypes for the High Mobility Multipurpose Wheeled Vehicle, or Humvee.
In early field trials, the Army liked what it saw and began ordering the Humvees by the thousands. The vehicles replaced the Jeep and other light military vehicles in logistics, support, transport and armed patrol roles. The vehicle even inspired a civilian car brand and other military adaptations.
The Humvee’s popularity grew during the Gulf War, where it easily navigated the desert terrain. But the Iraq War revealed that the unarmored Humvee was vulnerable to improvised explosive devices, or IEDs, which killed 67 US troops in the first four months of the conflict. In response, the Army hastily up-armored select models and replaced them in frontline service with the more-armored MRAP.
But the Humvee has continued to perform well in its mission-critical roles. It’s conquered mud, sand and rocks, evaded detection in the desert, pulled trailers on the highway, and jumped entire continents with Marine Expeditionary Units. The funny-looking 4×4 has been a hot-rodded Jeep when the military needed an off-roader, and it’s been an armored outpost when they need a shelter.
The HMMWV remains the most versatile military vehicle in the world. Its design has influenced other military and civilian vehicles, and its reputation for durability and reliability have earned it a global following. But the Humvee’s time in the limelight may be coming to an end. The 1st Armored Brigade Combat Team at Fort Drum in New York state has started receiving the first batches of the Joint Light Tactical Vehicle (JLTV)—the Humvee’s frontline replacement.
Engines
The military version of the Humvee (High Mobility Multipurpose Wheeled Vehicle; colloquially called the Hummer) is a light four-wheel drive, armored truck that has replaced many of the roles played by the jeep. It is a highly versatile platform that can be easily modified to fulfill the needs of different battlefield situations. It can be adapted to carry medical equipment, weapons, ammunition and other supplies. It is also capable of operating in harsh environments and off-road.
Aside from the increased capacity, the Humvee is remarkably similar to its civilian counterpart. It has four-wheel drive, a high center of gravity and a full range of onboard equipment. It can accommodate a team of six soldiers, and it has an impressive payload capability of more than 2,500 pounds under combat conditions.
In order to support such a large payload, the engine in the Humvee must produce a significant amount of torque. The initial models used a naturally aspirated 6.2L GM diesel engine, later upgraded to a turbocharged version. While these engines are certainly capable of moving the vehicles around, they are not known for their performance. A Banks chassis dyno test showed that a turbo 6.5L equipped Humvee produces only 113 horsepower at 3200 RPM and 219 lb-ft of torque at 2600 RPM.
One of the main drawbacks to military vehicles is their limited top speed on the highway, which can be frustrating for those who love to drive fast. However, they make up for this shortcoming on the dirt roads, where their rugged suspension and low gearing shine through.
Another drawback of the Humvee is its complex electrical system, which requires specialized training to work on. The vehicles are also quite expensive to maintain, but AM General has found ways to reduce the cost of maintenance. It developed a reliability extension kit in 2006, which includes new components such as a geared fan drive, new cool pack and shroud, new shock absorbers, A-arm bushings and a re-engineered geared hub assembly.
Transmissions
The HMMWV or Humvee as it is more commonly known has become the face of the US Military (all branches) and easily the most recognized piece of military hardware ever developed. It has supplanted many of the other military vehicles in use at the time, such as the jeeps and various trucks. It is the most ubiquitous vehicle used by any branch of the US Military and can be seen in nearly every patch of dry land on the planet.
It has 15 different configurations (cargo/troop carriers, weapons carriers, ambulances and shelter carriers) but all share a common chassis, engine and transmission with 44 interchangeable parts. The Humvee can also mount a gun turret, which is usually outfitted with a.50-caliber machine gun or Mark 19 automatic grenade launcher for armed patrols and reconnaissance missions.
Humvees have full time four wheel drive and double wishbone independent suspension at each corner which allows for 16 inches of travel per wheel. This aggressive setup makes them capable of traversing some pretty radical terrain. However, the factory suspension system is not up to the task of carrying all of the extra sprung weight that an Up-Armored Humvee has and this is why so many military vehicles are fitted with Gale Banks Suspension systems when they are upgraded for a mission.
The Army is currently in the process of replacing the aging fleet of Humvees with their new Joint Light Tactical Vehicle or JLTV. The JLTV is designed to be more reliable and better equipped for the kinds of tasks that a platoon of soldiers would typically perform. The Army has brought 22 up-armored Humvees to test alongside Oshkosh, Lockheed Martin and AM General’s JLTV entrants to ensure that the new vehicles are up to the task.
Safety
Despite its reputation for being a gas-guzzler, the Humvee is well suited to off-road use. Its independent front and rear suspensions allow it to navigate rough terrain that would stop other four-wheel drive vehicles in their tracks. Its advanced shock absorbers and torque-biasing differentials help the vehicle grip the ground, making it extremely maneuverable on rocky or sandy surfaces. Its low center of gravity and heavy-duty suspension give it impressive angles of approach, departure, ramp breakover and grade and side slope capabilities.
Humvees can be customized to suit specific purposes, such as carrying cargo or mounting weapons. However, this added weight puts a strain on the engine and transmission. It also increases fuel consumption and makes it more difficult to find parts. It can also be difficult to maintain if used off-road, as the terrain and weather conditions it faces are not conducive to regular maintenance.
The military is replacing some of its fleet with the newer Joint Light Tactical Vehicle, but it will keep many Humvees in service as an insurance policy against the next big fight. The service plans to add some safety measures, including anti-lock brakes and electronic stability control kits to the vehicles.
FORT EUSTIS, Va. — As the Humvee rolled over, the driver and passengers held themselves up with their hands pressed firmly against their armor-clad chests. During training at Fort Eustis on Feb. 27, the crew performed a controlled rollover to simulate what could happen in real life. Researchers say the findings suggest that soldiers might need more protection inside their Humvees, especially gunners. They recommend training in combat-like situations through simulation or live-training exercises, and they propose adding devices for safety in rollover crashes.