Which item is not a common cause of skid for fire apparatus?

• A. Changing lanes
• B. Anticipating obstacles in the road
• C. Weight transfer
• D. The brake limiting valve

Answer: (D)

Skids happen when tires lose traction and can’t hold the vehicle’s path, usually from inputs that exceed what the tires can grip. In fire apparatus, abrupt steering (changing lanes) or sudden avoidance maneuvers (anticipating obstacles) push the tires beyond their grip, creating lateral slip. Weight transfer is a key factor: braking shifts weight forward, reducing rear-tire traction, while accelerating or decelerating can alter how much grip each axle has, making skidding more likely if inputs are aggressive or mis timed.

The brake limiting valve is designed to prevent wheel lock by modulating braking pressure on heavy vehicles. By keeping wheels from locking up, it helps maintain directional control and traction, rather than causing a skid. That’s why it’s not a common cause of skid.