CDL Combination Vehicles TestCombination Vehicle Air BrakesHard
You are making a sharp turn in a combination vehicle. Which of the following braking techniques is generally recommended to prevent a skid, especially if the road surface is slippery?
- ASteering and braking simultaneously with light, steady pressure.
- BApplying the trailer hand valve to slow the trailer first.
- CReleasing the accelerator and lightly applying all brakes, maintaining steering control.
- DDownshifting aggressively to use engine braking, avoiding the foot pedal.
Show answer & explanationAnswer & explanation
Correct answer: C. Releasing the accelerator and lightly applying all brakes, maintaining steering control.
When making a sharp turn on a slippery surface, the best technique is to reduce speed before the turn by releasing the accelerator and applying light, steady brake pressure, while maintaining steering control. This minimizes the risk of a jackknife or trailer skid by avoiding sudden weight shifts or locking wheels.
Why the other options are wrong
- A. Braking while turning, even lightly, on a slippery surface can still cause a skid. It's better to slow down before the turn.
- B. Applying the trailer hand valve alone can cause the trailer to skid or jackknife, especially in a turn.
- D. Aggressive downshifting can cause the drive wheels to lock or skid, especially on slippery surfaces, leading to loss of control.
Slippery Turn Braking (Combination)
To prevent skids or loss of control in a combination vehicle when turning on a slippery surface, it is best to slow down before the turn using light, steady braking and engine braking, while maintaining full steering control.
- Reduce speed *before* the turn.
- Use light, steady brake pressure.
- Maintain steering control throughout the turn.
- Avoid sudden, aggressive inputs.
Memory trick: Slippery turn? 'Slow' before, then 'Steer' through.