Question 33 of 140

Your combination vehicle experiences a total loss of service brakes while driving. What should you do?

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Turn off the engine immediately while still at highway speed
Use the parking (emergency) brake system and downshift, steering toward an escape route or safe area to stop
Shift into the highest gear available to slow down faster
Continue driving normally, since air brake systems on a combination vehicle cannot fail completely under any circumstance

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Correct answer to question 33 (Combination Vehicles): Use the parking (emergency) brake system and downshift, steering toward an escape route or safe area to stop

Why

With the service brakes gone, the spring/parking brake system and a lower gear are what's left to slow the vehicle, combined with steering toward the safest available place to stop.

Updated: November 2026

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Your combination vehicle experiences a total loss of service brakes while driving. What should you do?

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