The combustion pressure in diesel engine cylinder rises intensely and the maximum pressure is extremely high compared with a gasoline engine, because of the differences in the combustion methods (see Diesel Engines and Gasoline Engines (2) ). As a result, diesel engines generally produce more noise, vibration and harshness (NVH) than gasoline engines, and this is a major complaint among diesel users. Isuzu is making efforts to reduce the NVH to the level of gasoline engines by making full use of the latest technology.

The maximum cylinder pressure in diesel engine is considerably high and the pressure rise during combustion is very rapid, causing the engine vibration and noise. Also, diesel engine components such as the piston are solidly built in order to endure the high pressure and pressure increase ratio. The extra weight of these components translates into increased inertia, the scale of vibration. It is possible to control noise generation by reforming the engine structure to absorb vibration and to reduce the overall level of vibration. Moreover, vibration travels from the piston to the connecting rod, crankshaft and engine block. This form of vibration can be attenuated by employing a ladder frame structure with a more rigid crankshaft bearing.