What can cause understeering in a commercial vehicle?

Understeering in a commercial vehicle occurs when the vehicle does not turn as much as the driver intends, often resulting in a situation where the vehicle continues to move forward instead of following the desired path through a turn. Carrying too much speed into a turn is a key factor that leads to this condition.

When a driver approaches a turn too quickly, the vehicle's centrifugal force increases, which can overwhelm the steering capability. This causes the front tires to lose grip and the vehicle to essentially "plow" straight ahead rather than turning. The combination of speed and the dynamics of the vehicle can lead to a loss of control, making it difficult for the driver to navigate through the turn as intended.

In contrast, while poor tire traction can contribute to handling difficulties, it's typically not the sole reason for understeering; it's generally a combination of speed and road conditions. A high center of gravity might affect the overall stability of the vehicle and its handling characteristics, especially in larger vehicles, but the immediate cause of understeering is mainly tied to excessive speed during a turn. Driving too slowly can actually prevent understeering, as it allows for better control of the vehicle through a turn.