| M55 | |
|---|---|
 M55 howitzer in the US Army Ordnance Museum | |
| Type | Self-propelled artillery |
| Place of origin | United States |
| Service history | |
| In service | 1952–1960s (United States) |
| Used by | United States Belgium Turkey Spain West Germany Republic of China |
| Wars | Vietnam War Second Taiwan Strait Crisis |
| Production history | |
| Manufacturer | Pacific Car and Foundry Company |
| Produced | 1950s |
| Specifications | |
| Mass | 44 metric tons |
| Length | 9.75 m |
| Crew | 6 |
| Armour | 25 mm (maximum) (Rolled homogeneous armour) |
Main armament | 203.2 mm M47 howitzer (10 rounds) |
Secondary armament | .50 cal M2HB machine gun (900 rounds) |
| Engine | Continental AV1790-5B (12 cylinder, 4 cycle, 90° vee gasoline) 810 hp at 2800 rpm (gross) 704 hp at 2800 rpm (net) |
| Transmission | Allison CD-850-4A (two ranges forward, one reverse) |
| Suspension | torsion bar |
Operational range | 160 mi (260 km) |
| Maximum speed | 30 mph (48 km/h) |
The M55 is an American fully enclosed and armored self-propelled howitzer based on the M53 155 mm self-propelled gun and with components taken from the M47 Patton.