USSOCOM Ground Mobility Vehicle (GMV)
Desert Mobility Vehicle (DMV)/"Dumvee"

The US Special Operations Command Ground Mobility Vehicle effort modified the basic High Mobility Multi-purpose Wheeled Vehicle (HMMWV) into one of 4 GMV variants: GMV-R (Ranger) and GMV-S SOF for the US Army Special Operations Command; GMV-N (Navy) for the Naval Special Warfare Command; and GMV-M (Marine Corps) for the Marine Corps Forces Special Operations Command.

The objective of the GMV program was to provide SOF with a mobility platform capable of infiltrating and operating in low- or mid-intensity conflicts over varied terrain while significantly improving Special Operations Forces' capability to travel unassisted over long distances.

The GMV-N was a SEAL-specific humvee that employed a multitude of weapons and was fitted with a modular armor kit. Depending on the mission, armor could be added or removed to either increase speed and maneuverability or increase protection. The GMV-N could carry up to 5 Operators. Every member of a SEAL team completed an intensive, 4-week tactical ground mobility training course where they learned the limitations of the vehicle, basic maintenance and tactical driving skill sets.

The Ground Mobility Vehicle program was the outgrowth of Special Operations HMMWVs developed as a by-product of deployments to the Middle East, as well as lessons learned during CONUS training. Initially the vehicles were primarily intended to provide equipment required to conduct mounted operations in desert environments. The Desert Mobility Vehicle System (DMVS) project began in 1985 and ended 5 years later with the development of modified vehicles, tactics, and doctrine, in the form of the training circular "Special Forces Mounted Operations."

The project was intended to enable 5th Special Forces Group (Airborne) to conduct joint and unilateral mounted operations in desert environments using specially modified HMMWVs, trailers, satellite navigation equipment, and desert mobility motorcycles. The HMMWV component was referred to as the Desert Mobility Vehicle (DMV), also referred to as the "Dumvee," a name that was subsequently used to refer to other Special Operations HMMWV types regardless of origin. These initial vehicles were based on M998 and M1026 HMMWV types. The vehicles were subsequently used during the first Gulf War in 1991 and in Somalia in 1992-1993.

In early FY03, as war approached, US Army Special Operatiosn Command turned to Letterkenny Army Depot to accelerate production of GMVs. Letterkenny had established a special relationship with USASOC in 1998 with the production of GMV kits for the specially modified HMMWVs. When USASOC made its urgent request known to the depot, depot managers decided to employ their newly formed Lean team to make improvements in the GMV process. The first task was to transform the depot's existing GMV maintenance and rebuild production line. The initial goal was to turn new humvees into GMVs within a 10-week turnaround time, measuring from when a vehicle came in the door to when it went out the door. Before the project could be completed, the requirement quickly changed to a turnaround time of 3 weeks.

As USASOC's requirements changed, Letterkenny successfully ramped up production to 24 vehicles a week. Turnaround time was reduced from 10 weeks to 3 weeks and then to just 8.8 days, and the floorspace required for the operation was reduced by 50 percent. Not only was the depot able to supply the warfighter with vehicles in a greatly reduced time, it also provided the customer with savings of $990,000. The depot used the savings generated to produce 18 more GMVs and thus provide USASOC with an additional fighting capability that previously had been unfunded.

Efforts to improve the GMV family included a suspension upgrade that returned some of the pre-armor payload capacity, an issue with all up-armored configurations of the HMMWV, and a significant standardization effort to consolidate the multiple configurations of the GMV into a single SOF GMV with a heavy and light configuration based on the threat environment. USSOCOM planned to begin fielding the suspension upgrade in 2008.

As of 2009, an emerging requirement was for the joint light tactical vehicle, which was to be a general replacement vehicle for HMMWV vehicles.