M1113/XM1113 HMMWV Expanded Capacity
The M1113 HMMWV has a gross vehicle weight of 11,500 lbs. TACOM developed the M1113 Expanded Capacity Vehicle (ECV), a HMMWV shelter carrier with strengthened suspension, drive train, and braking systems. As a result, the available vehicle payload is increased to 5,150 lbs, more than enough to handle projected CECOM load requirements.
The S-788 Lightweight Multipurpose Shelters (LMS) mounted on the original M1037 and M1097 HMMWVs cannot carry a fully configured shelter (weight rating = 3,300 lbs) because the combined shelter/crew/trailer pintle load weights exceed available HMMWV payload (4,400 lbs). As a result, materiel developers either remove excess equipment from their shelters and/or add additional HMMWV "chase vehicles" to carry the additional equipment. This situation came to a head in one particular case where the system exceeded the HMMWV rating by 30 lbs but was refused an overload waiver by DCSOPS. As an alternative to removing mission equipment, materiel developers should consider replacing the M1037/M1097 with a prime mover with a higher rated payload- the M1113 Expanded Capacity Vehicle (ECV).
