The crankshaft is a critical component in internal combustion engines, responsible for converting the reciprocating motion of the pistons into rotary motion. Its design and performance directly influence the engine's durability, efficiency, and operational smoothness. In multi-cylinder engines, crankshafts are subjected to complex loads and dynamic conditions, making them vulnerable to fatigue and vibration-induced failures. This study focuses on understanding the vibration characteristics and fatigue behavior of engine crankshafts, employing both theoretical and computational approaches to ensure reliability under real-world operating conditions.