The Mercedes OM403 is a V-shaped engine with ten cylinders. This device was primarily installed on trucks and was created in the early 1970s.

This model’s engine has a unique modular layout that lowers the engines’ prime cost. The Mercedes OM403 engine uses regular water as a coolant, which reduces operating costs but also raises the possibility of issues and malfunctions related to the impact of water on engine components.
With a working area of 15.9 liters, Mercedes OM 403 10-cylinder engines can produce 320 horsepower (235 kW). There are two valves on each cylinder. These motors are very dependable and efficient.
Specifications
| Engine’s type | diesel |
| Also called | OM 403 |
| Production years | 05/1974 |
| End of release | 09/1983 |
| Power output, hp / kW | 320 / 235 at 2500 rpm |
| Displacement, cc | 15900 |
| Number of cylinders | 10 |
| Valves | 20 |
| Torque output, Nm / rpm | 1600 |
| Compression ratio (compression) | 17.2:1 |
| Cylinder bore, mm | 125 |
| Piston stroke, mm | 130 |
| Crankshaft bearings | 6 |
| Configuration | V |
| Fuel type | diesel |
| Fuel system | inline injection pump |
| Cylinder head | OHV |
| Timing mechanism | spur gear |
| Timing | rocker arm |
| Cooling | water |

The Mercedes OM 403 engines are versatile in terms of gearbox compatibility due to their high power at low revs.
There are numerous uses for the motors themselves. These include trucks, municipal vehicles (like garbage trucks), and construction loaders. In addition, the OM403 works flawlessly with a variety of chassis, axles, and braking systems.
Engine Modifications
- OM 403.900 with 184 kW (250 HP);
- OM 403.905 with 236 kW (320 HP). Issue 9/1970 – 5/1975. For models MB 1932, 1632, 2232, 2032;
- OM 403.906 with 184 kW (250 HP). Issue 1/1969 – 4/1972. For models MB F 193, F 263, F 463;
- OM 403.910 with a capacity of 184-236 kW (250-320 hp). For MB Comfort class 400 – S211, 400 – S215;
- OM 403.911;
- OM 403.915 with 236 kW (320 HP). Issue 1/1972 – 12/1975. For models MB 1932, 1632, 2232, 2032;
- OM 403.916 with 236 kW (320 HP). Issue 5/1974 – 9/1983. For models MB 1932, 2632, 1632;
- OM 403.917 with 236 kW (320 HP). Issue 4/1972 – 12/1974. For models MB F 130, F 193, F 263;
- OM 403.918 with 236 kW (320 HP). Issue 7/1975 – 6/1983. For models MB O 303 – O 303;
- OM 403.919 with 236 kW (320 HP). Issue 4/1972 – 12/1974. For models MB F 130, F 193, F 263;
- OM 403.930 with 236 kW (320 HP). Issue 4/1972 – 12/1974. For models MB F 130, F 193, F 263;
- OM 403.931 with 236 kW (320 HP). Issue 8/1973 – 9/1983. For models MB 1932, 2632, 1632, 2232;
- OM 403.932 with 236 kW (320 HP). Issue 5/1974 – 9/1983. For models MB 1932, 2632, 1632, 2232, 2032;
- OM 403.933 with 261 kW (355 HP). Issue 8/1973 – 9/1983. For MB 2632;
- OM 403.934 with 236 kW (320 HP). Issue 4/1972 – 12/1985. For models MB 1932, 1632, 2232;
- OM 403.935 with 261 kW (355 HP). Issue 8/1973 – 9/1983. For models MB 1932, 1632, 2232.
