Ontario Class A Practice Test · Question
A 'jackknife' occurs when:
Drive-wheel lock-up or skid causes the trailer to swing around and form an angle with the tractor.
Start free practice for Ontario Class A Practice Test
50 questions · no signup required · 40 free questions per day
Question: A 'jackknife' occurs when:
Answer options: ✅ The tractor and trailer fold at the fifth wheel due to drive-wheel skid
- Tires lose air pressure suddenly
- The trailer load shifts forward
- The kingpin breaks
Correct answer: The tractor and trailer fold at the fifth wheel due to drive-wheel skid
Explanation: Drive-wheel lock-up or skid causes the trailer to swing around and form an angle with the tractor.
Start free practice for Ontario Class A Practice Test
50 questions · no signup required · 40 free questions per day
More about Ontario Class A Practice Test
Related Questions
- Approaching a sign that reads 'Runaway Lane / Emergency Escape Ramp Ahead', what is the immediate significance
- A rectangular sign with a truck symbol and an upward-pointing arrow, followed by 'Steep Grade', combined with
- What is the correct interpretation of a 'Oversize Load' sign displayed on a pilot vehicle in front of a flatbe
- A commercial vehicle displaying a red flag at the rear of its load indicates:
- You see a rectangular yellow sign with 'LONG VEHICLE' written in black letters. What information does this con
- A sign on the side of a transport truck reads ‘WIDE LOAD’. Which of the following is most probable about the v
More for Ontario Class A Practice Test candidates
Practice tests
Question explanations
- Approaching a sign that reads 'Runaway Lane / Emergency Escape Ramp Ahead', what is the immediate significance
- A rectangular sign with a truck symbol and an upward-pointing arrow, followed by 'Steep Grade', combined with
- What is the correct interpretation of a 'Oversize Load' sign displayed on a pilot vehicle in front of a flatbe
- A commercial vehicle displaying a red flag at the rear of its load indicates:
Ready to practice?
Free, no signup required. Build a wrong-question list as you go.
Start Free Ontario Class A Practice Test Practice →Related courses
Other Canadian certifications candidates often prepare for alongside this one.