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Single-piece construction was used for the cylinder block bottom wall. The bottom wall serves as the crank case and the crank shaft support area bearing cap. This feature allows the end result of further increasing the rigidity of the crank shaft support area.

The main bearing is the component that supports the rotational force and pressure of the crank mechanism. The importance of the main bearing is highlighted because this is where the energy of the combusted fuel gas pressure is converted into rotational motion. In order to most efficiently complete this task, sufficient strength is required. The ladder frame approach allows for this additional stiffness.

The Isuzu 6H ladder frame construction is effective in minimizing the cylinder block bending moment and countering the vibration mode which tries to deform the bearing. The resulting rigidity has is felt on through to the transmission, which significantly helps the engine noise and vibration.

Both an experimental model analysis and FEM frequency response analysis were conducted during the design stage to optimize the final structure of the ladder frame engine block. The results of the computer simulations were that they both raised the vibration and noise into the high frequency range. This movement of the noise to higher frequencies resulted in better vibration and sound characteristics of the engine.