The crankshaft is the key component of the shale gas fracturing truck's diesel engine. Mass imbalance due to errors in the manufacturing process and other damage caused by long periods of operation can cause vibration for the crankshaft vibration problem. The static analysis is carried out based on the ignition condition of the second cylinder. The modal analysis of the crankshaft is then carried out. The modal analysis showed that resonance could cause significant deformation of the crankshaft. Consequently, harmonic response analysis, stochastic vibration analysis, and topology optimization were carried out on the crankshaft. The results show that the modes of each order of the crankshaft of the fracturing truck diesel engine are diverse. The modal amplitude is large. Fatigue damage is easily generated. After optimization, the mass of the crankshaft is reduced, the first natural frequency is increased, and the crankshaft is far away from the resonance interval while avoiding resonance failure. This document provides theoretical guidance for the design, optimization, research, and development of crankshafts.