The standardized 5-ton M39 series was produced by the AM General Company a short time, gathering the last of 112 thousand trucks in this range. As early as 1970, constructors of other manufactures begun to develop a new updated range, but this work was completed by the AM General Company. At the end of 1971, in South Bend, producing of the new 5-ton range M809 (6×6) with GVW 14,0-15,2 t was begun. It was equipped with a new Cummins NHC250 diesel engine (14,0 l, 243 hp), mechanical 5-speed gearbox, dual main gear, hydro pneumatic braking system, steering booster and 24-volt electrical equipment.
The next versions were produced:
- M809 – basic chassis 6×6 with the long wheel base (4547 mm).
- M810 – basic chassis 6×6 with the short-wheelbase (4242 mm).
- M811 – basic chassis 6×6 with the extra long wheel base (5461 mm). One of the bodies was SEORTM with opening side parts looks like wings. Inside the body were different kinds of tools – lathes, drill presses, rubbing machines, welding machines, etc.
- M812 – chassis 6×6 with the extra long wheelbase (5461 mm) designed for the transportation section of the bridge. Also, was a rocket launcher version.
- M813 – flatbed truck 6×6 on the M809 chassis with a metal body with removable benches. There was a M813A1 version with a fold-out side boards.
- M814 – flatbed truck 6×6 on the M811 chassis with a metal body with removable benches.
- M815 – pipe truck 6×6 for transportation of pipes, logs or sections of a bridge. It had a fortified cabin and used together with a M796 trailer.
- M816 – recovery vehicle 6×6.
- M817 – tipper 6×6 with a 3.8-cc body.
- M818 – tractor 6×6.
- M819 – crane 6×6.
- M820 – van 6×6. The next versions were produced: M820 – with windows, heating, air conditioning, power from an external source; M820A1 – no windows and air conditioning, but with heating; M820A2 – with windows, heating, air conditioning and hydraulic lift.
- M821 – truck 6×6 used for transportation of the bridge sections.
The intake on the M809 series trucks was located on the left side of the hood, while on the M39 trucks – on the right side. The M809 series had the same cab as the M39, but the hood was longer to accommodate the more powerful engine. In the U.S. Army the 5-ton medium tactical vehicles (MTV) of the FMTV series replaced remaining M-809 series trucks in the early 1990s, while in the U.S. Navy and Marine Corps the Medium Tactical Vehicle Replacement (MTVR) superseded both the M-809 and M-939 series of trucks after 1999.
Predecessor: Kaiser-Jeep M809
Successor: AM General M939
Asia KM250 / KM500