A three-axle delivery vehicle is descending an exit ramp when the driver suddenly senses violent rhythmic shuddering and the rear of the vehicle begins to sway laterally, without any pull felt in the steering column. Which of the following correctly identifies the failure taking place and the mandatory immediate driver action?
- AThe event indicates a steer-axle tire blowout; the driver should immediately downshift two gears and apply rapid, hard pulses on the brake pedal to halt the vehicle within the travel lane.
- The event indicates a rear drive-axle tire failure; the driver should stay off the brakes, maintain straight steering direction, and allow natural deceleration to slow the vehicle before gently moving onto the shoulder.Answer
- CThe event indicates a drive-axle tire blowout; the driver should immediately activate the auxiliary engine retarder and steer sharply into oncoming traffic lanes to counteract the yaw motion.
- DThe event indicates steer-tire tread separation; the driver should accelerate firmly to equalize steer axle rotation, then perform an abrupt steering maneuver toward the median.
Answer
The condition indicates a rear drive-axle tire failure; the driver must stay off the brakes, keep the steering wheel steady to track straight, and allow the vehicle to coast down before gently braking onto the shoulder.
A rear-tire failure is distinctively signaled by severe vibration and lateral swaying or fishtailing at the rear of the vehicle, without the strong steering wheel pull characteristic of a steer-tire failure. In any blowout emergency, the driver must never brake abruptly; the correct protocol is to stay completely off the brake pedal, maintain directional control, allow the vehicle to coast down naturally as speed drops, and then brake very gently once safely on the shoulder.
Step-by-Step Solution
Key Concept
Tire Failure Identification and Blowout Response
Estimated Time:1m 30s