Specific: 24 M578´s bought in
1966 - 1970 as ARV for the M113/M113A1 APC and the M109.
Historical: The Pacific Car and Foundry Co. was
awarded a US Army contract to design a new range of
self-propelled guns in 1956. The gun were the 175 mm
T235, the 203 mm T236 and the 155 mm T245. In 1957 the
program was expanded to include ambulances (T119) and
armoured light recovery vehicles (T120).
Both the T119 and the T245 was dropped on the prototype
The chassis was designed around a Continental
eight-cylinder petrol engine, but was modified to accept
a General Motors diesel engine in 1959 as part of a
general trend in the US Army. It retained, however, the
Allison cross-drive automatic transmission.
The suspension system, torsion bar style, was enhanced by
a sort of combined spring-cum-shock absorber that works
on the hydraulic principle and has the facility, operated
by the driver, to entirely lock-out the suspension so
that, when a self-propelled gun is in the firing mode,
the chassis is a firm base and does not leap about all
over the place.
One feature of the M107/M110 high powered artillery was
the rapid barrel wear and the consequent need to be able
to change the barrels frequently and simply. The Pacific
Car and Foundry Co.developed the M578 (T120) for this
purpose. It incorporated a 27 tons capacity primary winch
which gave it a recovery as well as a lifting potential.
A secondary winch attached to the crane had a capacity of
13 tons, which was sufficient to lift the turret of a
medium tank of the period.
It has a armoured turret, which can be traversed through
a full 360 degrees, with a boom rather than a gun barrel.
Build on the M107/M110 chassis by FMC and other
manufacturers from late 1962.
Production was originally completed in the late 1960s,
but in 1975 the M578 was placed back in production by
Bowen-McLaughlin-York (now United Defence).
Length: 6.40 m (249 inches).
Width: 3.16 m (123 inches).
Height: 3.32 m (129 inches).
Weight: 24.500 kg (53.900 lb.).
Armour: 13 mm (0.5 inches).
Engine: V8-cylinder Detroit Diesel, type 8V71T, 9.287
cm3 (566 cubic inches), supercharged, liquid cooled.
Horsepower: 405 at 2.300 rpm.
Transmission: Allison XTG-411-2A powershift
cross-drive with 4 forward and 2 reverse gears
Transfer case: None.
Electrical system: 24 volt, negative ground.
Brakes: Multiple disc.
without preparation: 1.1 m (42 inches).
with deep water fording kit: N/A.
Fuel type: Diesel.
Fuel capacity: 1135 liter (250 gallons).
Range: 725 km (453 miles).
Armament: Armed with a 12.7 mm (cal.
0.50) machine gun with 500 rounds.
Additional: Also used by Bolivia,
Brazil, Canada, Egypt, Iran, Jordan, Morocco, the
Netherlands, Norway, Philippines, Saudi Arabia, Spain,
United Kingdom and USA.
Max. speed 60 km/h (37 mph).