The USMC does not use the HEMTT or PLS, and the Army does not use the LVSR, but both services use a common trailer (M1076) with all three truck types.

Following the evaluation of proposals submitted by AM General, MAN, Pacific Car & Foundry (PACCAR) and Oshkosh Truck Corporation (with PACCAR–GMC team being the apparent leader of the competition, with pre-production assembly line already established)[7] in May 1981, the then U.S. Army Tank-Automotive Command awarded an initial five-year contract valued at US$251.13 million to Oshkosh Truck Corporation for production of the 10-short-ton (9,100 kg) 8×8 Heavy Expanded Mobility Tactical Truck (HEMTT).

[4] The first prototype HEMTT was completed in December 1981, pre-production examples followed during March 1982, with the first production vehicles produced in September 1982.

Contract options allowed for up to an additional 5,351 HEMTTs to be ordered, bringing production totals to 7,490 vehicles.

[8] The Family of Heavy Tactical Vehicles (FHTV) contract was awarded to Oshkosh by the U.S. Army in March 2001.

According to the October release, the government intends to award a five-year requirements contract with an estimated value of US$822 million on a sole source basis to Oshkosh Corporation.

[4] On 19 June 2015, Oshkosh Defense announced the U.S. Army had awarded the company a five-year requirements contract worth a potential $780 million to Recapitalize (Recap) its Family of Heavy Tactical Vehicles (FHTV).

HEMTT models account for around 75 per cent of the Recap potential, and all work performed under the contract will be completed in Oshkosh, Wisconsin.

[4] In April 2017, Oshkosh announced further FHTV 4 awards valued at more than $258 million for the Recap of 670 FHTVs plus the production of 356 PLS trailers.

[9] On 23 May 2018 Oshkosh announced a further FHTV-4 award, this valued at $235.2 million for the Recap of 410 FHTVs and the manufacture of 680 new PLS trailers.

[10] On 8 February 2019 Oshkosh announced an FHTV-4 award valued at $225.7 million for the Recap of 407 FHTVs and the manufacture of 601 new PLS trailers.

[2] Used vehicles can be returned to Oshkosh as part of a recapitalization program where they are stripped to their frame rails and then fully rebuilt to a zero-hour, zero-mile, like-new condition.

Recapitalized vehicles are returned to the Army with a new bumper-to-bumper warranty and include air-conditioned and armor-ready cabs; electrical upgrades, and an anti-lock braking system.

Parallel to the FHTV 4 extension effort, the U.S. Army's Heavy Tactical Vehicles (HTV) PEO CS&CSS issued on 20 July 2020 Notice ID W56HZV-20-R-0237, a Request for Information (RfI) for the Next Generation Future Truck (NGFT).

[2] The HEMTT's objective is to provide heavy transport capabilities for supply and re-supply of combat vehicles and weapons systems.

Compared to earlier generation 5-ton trucks in U.S. Army service it offers increased payload and mobility.

An EPA 2004 compliant Caterpillar (CAT) C-15 six-cylinder, 15.2-liter diesel developing a peak of 515 hp (384 kW) is fitted to HEMTT A4 models.

HEMTT A0 and A1 models are fitted with an Allison HT 740D 4F/1R automatic transmission, torque converter, and Oshkosh 55,000-pound (25,000 kg) two-speed transfer case.

HEMTT A4 models are fitted with an Allison 4500SP 5F/1R automatic transmission and an uprated version of Oshkosh's 55,000-pound (25,000 kg) two-speed transfer case.