Qassim General Dept. of Traffic Truck & Bus
Practice mode· Heavy vehicle skillsQassim General Dept. of Traffic - Saudi Heavy Vehicle Skills Test 2
Second set of heavy-vehicle questions covering coupling, tunnels and bridges, passenger safety, hill starts and managing long or wide loads. Complete both tests for full coverage.
What does the low air-pressure warning light or buzzer on a heavy truck indicate?
The other 12 questions in this test
Read them all. The answer and the reason for each, and the timed 22-question run, are in the Saudi Driving Theory Online Practice Bank.
- Q11Heavy vehicle
When should a heavy truck driver engage the differential lock on the drive axle?
- AOn all motorway driving to improve stability at high speed
- BWhen descending steep hills to improve braking
- CWhenever the vehicle is loaded to maximum gross weight
- DOnly when one or more drive wheels are spinning on a slippery or soft surface and the vehicle cannot move; it must be disengaged as soon as traction is regained
Answer and explanation in the bank
- Q12Heavy vehicle
A driver is climbing a steep grade in a split gearbox truck and needs to change from 5-Hi to 6-Lo. What is the correct sequence?
- AFirst move the range switch to Lo, then wait for the gearbox to change range automatically before moving the main lever
- BFully depress the clutch, select neutral, change the range switch, release the clutch, then re-depress the clutch and select 6
- CRange changes should never be made on uphill gradients; pull over and stop first
- DAt the correct engine rev for the upshift, move the main lever to position 6 while simultaneously pre-selecting Lo on the range switch; the change completes cleanly mid-shift
Answer and explanation in the bank
- Q13Heavy vehicle
What is the kingpin on an articulated trailer?
- AThe central locking pin that holds the trailer's cargo doors shut during transit
- BA safety pin that prevents the landing legs from accidentally folding while the trailer is coupled
- CThe pin that connects the service brake air line to the trailer brake system
- DA steel pin on the underside of the trailer's front skid plate that locks into the fifth wheel of the tractor unit to form the articulation joint
Answer and explanation in the bank
- Q14Heavy vehicle
A driver notices that the kingpin has visible wear and cracks after coupling. What action must be taken?
- ADrive only at low speed to the nearest workshop, because the kingpin is unlikely to fail completely on a short journey
- BLubricate the kingpin with grease and tighten the fifth wheel jaw to compensate for the wear
- CDo not move the vehicle; the trailer must be taken out of service for inspection and repair of the kingpin before it is used
- DComplete the current delivery and report the condition at the next scheduled maintenance
Answer and explanation in the bank
- Q15Heavy vehicle
Why are high-sided curtain-sided trailers especially vulnerable on exposed sections of Saudi highways during windy conditions?
- AWind vibrates the curtain fabric and loosens the load restraints
- BWind reduces the air pressure in the tyres, lowering traction
- CHigh-sided vehicles are not vulnerable to wind because their aerodynamic shape deflects air over the roof
- DThe large flat surface of the trailer acts as a sail, and strong crosswinds can generate enough lateral force to push the trailer sideways or cause rollover, especially when lightly loaded
Answer and explanation in the bank
- Q16Heavy vehicle
A driver is crossing an exposed bridge in a high-sided empty trailer when a sudden strong gust hits from the side. What is the correct immediate response?
- AReduce speed smoothly, grip the steering wheel firmly with both hands, steer gently to counteract the push, and do not make sudden swerving corrections
- BAccelerate to pass the exposed section of bridge as quickly as possible
- CApply the trailer brakes sharply to stabilise the trailer
- DSteer sharply into the wind to prevent the trailer from blowing off course
Answer and explanation in the bank
- Q17Heavy vehicle
How does extreme heat in Saudi Arabia affect truck tyre pressure during a long journey?
- AHeat causes tyres to deflate gradually, so pressure should be topped up at every fuel stop
- BTyre pressure is unaffected by temperature changes in a tubeless tyre
- CHot weather tyres should be inflated 50% above the cold specification to prevent overheating
- DTyre pressure rises significantly as the air inside heats up; tyres must be checked cold before departure, and pressure must never be released from hot tyres to bring the reading down
Answer and explanation in the bank
- Q18Heavy vehicle
During a summer crossing of a Saudi desert highway, a driver notices that one tyre on the trailer feels unusually hot compared with the others when checked at a fuel stop. What could this indicate and what should the driver do?
- AA binding or dragging brake, underinflation, or internal tyre damage causing heat build-up; the driver must not continue until the cause is identified and rectified to prevent tyre blowout or fire
- BIt is normal for one tyre to run hotter than others due to variation in road surface; continue the journey
- CInflate the hot tyre to maximum sidewall pressure and continue, as extra pressure will reduce heat generation
- DPour water over the tyre to cool it and then continue immediately
Answer and explanation in the bank
- Q19Heavy vehicle
When following another vehicle on a Saudi highway in a fully loaded 40-tonne articulated truck, what following distance approach should you use?
- AThe same two-second rule used for a light vehicle at the same speed
- BA gap well beyond the two-second rule, because heavy vehicles need far more distance to stop safely
- CA fixed 20-metre gap regardless of speed
- DOne vehicle length for every 10 km/h of speed
Answer and explanation in the bank
- Q20Heavy vehicle
You are driving a laden heavy truck at 90 km/h on a dry Saudi highway when the vehicle in front stops suddenly. Which factor most increases your stopping distance compared with a light vehicle?
- AThe high kinetic energy of the truck's greater mass, which requires much more braking force and distance to dissipate
- BThe longer wheelbase, which forces the rear wheels to travel further before locking
- CThe elevated driving position, which reduces the driver's ability to judge distance accurately
- DAir resistance acting against the front of the cab, which pushes the truck forward
Answer and explanation in the bank
- Q21Heavy vehicle
What type of braking system is fitted to most heavy trucks and buses operating in Saudi Arabia?
- AHydraulic disc brakes identical to those fitted on light vehicles
- BElectric regenerative brakes that charge the battery on every stop
- CPneumatic (air) brakes, which use compressed air to actuate the brake chambers
- DCable-operated drum brakes similar to those used on motorcycles
Answer and explanation in the bank
- Q22Heavy vehicle
What is brake fade, and which situation most commonly causes it on a heavy truck?
- AA sudden increase in braking force caused by air pressure building up too quickly in the chambers
- BA reduction in braking power caused by overheated brake drums or discs, most commonly on long downhill descents when brakes are applied repeatedly
- CThe delay between pressing the brake pedal and the air reaching the rear axle chambers
- DThe locking of the rear wheels caused by excessive brake pedal pressure on a slippery surface
Answer and explanation in the bank
Every answer above, with the rule it comes from, plus the full 22-question timed test.
Get the Saudi Driving Theory Online Practice Bank - SAR 39What this test covers
Topics include road signs, traffic signals, right of way, roundabouts, speed limits, seat belts, fines and penalties, and the safe-driving rules specific to your vehicle category. Full question-by-question feedback with explanations is shown immediately after you finish the test above.
Frequently asked questions
How many questions is the Qassim General Dept. of Traffic truck & bus theory test?
The official General Dept. of Traffic truck & bus theory test in Qassim has 35 questions and you need 22 correct (63%) to pass. This practice test has 22 questions.
Is this the real exam?
These are practice questions to help you revise, written to the published rules and to what candidates report from the real test. They are not the official Saudi exam and the real question bank, format, fees and pass mark are set by the General Department of Traffic (Moroor) and the driving schools, and can change. Always confirm the current requirements with your driving school or the traffic department.
Is this practice test free?
The first 10 questions are free, with no signup, and each shows the answer and the reason. The full 22-question test, timed, is in the Saudi Driving Theory Online Practice Bank (SAR 39, one payment), with every question in the bank.
What does the Qassim truck & bus theory test cover?
Road signs, traffic signals, right of way, roundabouts, speed limits, seat belts, penalties and safe-driving rules, plus the handling and safety topics specific to your vehicle.