Massachusetts RMV CDL General Knowledge Practice Test 5
Test 5 of 5. Pick an answer for each question to see if it is right and why; your score appears at the end. You need 40 correct answers to pass, the same ratio as the real Massachusetts test.
- Questions50
- Correct to pass40
- Passing score80%
- Minimum age18 years
-
1. Rust streaks are running outward from the lug nuts on one wheel. What does this most likely indicate?
Show answer
Answer C: The lug nuts may be loose
Rust trails spreading from the nuts are a classic sign that the nuts have worked loose and the wheel has been moving on the studs.
-
2. Which lamp must make the rear registration plate legible after dark?
Show answer
Answer C: A white lamp that lights the plate
A white license plate lamp is required so the plate can be read at night, and a burned out one is a defect like any other lamp.
-
3. What should you look for on the electrical wiring in the engine compartment?
Show answer
Answer A: Worn, frayed or cracked insulation and loose or corroded connections
Damaged insulation can short a circuit against the frame or engine, which can kill a lamp you depend on or start a fire.
-
4. What must the motor carrier do about a defect listed on a driver vehicle inspection report?
Show answer
Answer D: Repair it, or certify that repair is not needed, before the vehicle is dispatched again
A reported defect must be corrected, or certified as not needing correction, and that certification is what the next driver reads before taking the vehicle.
-
5. A car ahead of you keeps drifting within its lane and moving unevenly. What should you assume?
Show answer
Answer C: The driver may be distracted, lost or impaired
Unsteady lane keeping is a classic clue to a driver who is not in full control, so the safe response is to keep back and give plenty of room.
-
6. Your vehicle begins to hydroplane on a wet road. What should you do?
Show answer
Answer B: Release the accelerator and push in the clutch so the wheels can turn freely and regain grip
Hydroplaning tires are riding on water; slowing without braking lets them settle back onto the road and grip again.
-
7. What do the U-bolts on a leaf spring suspension do?
Show answer
Answer A: They clamp the spring assembly to the axle so it cannot move
U-bolts hold the spring pack tight against the axle, and a loose or broken U-bolt lets the axle slide out of place under load.
-
8. Why should high beams not be used in fog?
Show answer
Answer A: The light reflects back off the droplets and blinds you
Fog is made of water droplets that scatter light straight back at the driver, so a stronger beam makes the wall of glare worse rather than better.
-
9. During a stop you find a package in the trailer leaking an unknown chemical. What should you do?
Show answer
Answer C: Keep clear, keep others away and get help without touching the package
A driver without the training and equipment does not handle a leak; the job is to protect people from the material and get qualified help to the scene.
-
10. You have backed into the same loading bay every week for a year. How often should you still get out and walk to the rear before backing?
Show answer
Answer D: Every time, since the area can change while you are away from it
A familiar space is no guarantee; vehicles, pallets, people and overhead obstructions appear between one visit and the next, so you check on every occasion.
-
11. You have a part load that fills only a third of a long trailer. How should it be placed?
Show answer
Answer C: Spread out and centerd side to side, so the weight sits over the axles
A part load is spread over as much of the floor as possible and kept centerd, so no axle is overloaded and the vehicle stays balanced from side to side.
-
12. When turning left, what should a driver of a long vehicle do before beginning the turn?
Show answer
Answer B: Reach the center of the intersection so the rear wheels clear the corner
The rear wheels follow a tighter path than the front, so the vehicle must reach the center of the intersection before the turn begins.
-
13. Why does a load of live animals need special attention?
Show answer
Answer D: The animals move and lean, so the center of gravity shifts and the vehicle can be pushed off balance in a turn
A live load will not stay where it is put, and that movement changes the balance of the vehicle exactly when a curve is loading it most.
-
14. Within total stopping distance, what exactly is perception distance?
Show answer
Answer D: The distance traveled from the moment your eyes see a hazard until your brain identifies it
Perception distance covers only the time between seeing a hazard and recognizing it as a hazard, before any physical reaction begins.
-
15. You are told a posted bridge ahead has a weight limit lower than your gross weight. What must you do?
Show answer
Answer C: Take a route that avoids it, because a posted limit is a legal limit
A posted structure limit must be obeyed exactly as any other weight limit, so a heavier vehicle has to be routed around it.
-
16. Which vehicle is most likely to be pushed around by a strong crosswind?
Show answer
Answer B: An empty van trailer
A large flat side with very little weight behind it gives the wind the most surface and the least resistance, which is the empty van trailer.
-
17. Apart from the legal duty, what is the main practical reason for a thorough pre-trip inspection?
Show answer
Answer A: It finds problems that could cause a breakdown or a crash before the vehicle is on the road
A defect found in the yard is an inconvenience, while the same defect found at highway speed can be a crash, so the inspection is where problems are cheapest to fix.
-
18. Your speedometer stops working during the pre-trip check. How should it be treated?
Show answer
Answer D: As a defect, because the driver cannot judge and control speed without it
A working speedometer is required equipment, because judging speed by feel in a heavy vehicle is unreliable and speed governs stopping distance.
-
19. Which set of emergency equipment must be carried on a commercial motor vehicle?
Show answer
Answer D: A fire extinguisher, spare electrical fuses unless the vehicle has circuit breakers, and warning devices
The required kit is a properly charged and rated fire extinguisher, spare fuses when the vehicle uses them, and warning devices for a stopped vehicle.
-
20. The shipper hands you the placards for a load that needs them. Who puts them on the vehicle?
Show answer
Answer C: The driver, who must also make sure they are the correct ones and are readable
The shipper supplies the placards, but it is the driver who must place them on the vehicle and confirm that they match the load and can be read.
-
21. Where are regrooved, recapped or retreaded tires not allowed on a truck or truck tractor?
Show answer
Answer C: On the front steering wheels
Regrooved and retreaded tires are prohibited on the front wheels of a truck or truck tractor because a steering tire blowout is extremely difficult to manage.
-
22. What does the tachometer on the dashboard of a heavy truck show?
Show answer
Answer D: How fast the engine is turning, in revolutions per minute
The tachometer reads engine speed in rpm, which is what a driver uses to judge shift points in a vehicle with a manual transmission.
-
23. A carrier operates commercial vehicles every day of the week. What weekly on-duty limit applies to its drivers?
Show answer
Answer A: 70 hours in 8 consecutive days
The limit is 60 hours in 7 consecutive days for a carrier that does not run every day, and 70 hours in 8 consecutive days for one that does.
-
24. When must a post-trip inspection be made?
Show answer
Answer D: At the end of each day the driver operates the vehicle
The post-trip inspection closes out each driving day so that anything found is recorded before the vehicle is handed to the next driver.
-
25. What are you looking for when you check the hubs and wheel seals during the walkaround?
Show answer
Answer B: Leaking oil or grease, which can also contaminate the brake linings
A leaking hub seal starves the bearing of lubricant and the escaping oil or grease can soak the brake linings and cut braking power.
-
26. What is the danger of letting engine speed climb past the top of the rated rpm range before you shift?
Show answer
Answer B: You can damage the engine, so the shift should be made before that point
Every engine has a rated operating range; running above it can cause serious engine damage, so the upshift belongs at the top of that range, not beyond it.
-
27. What is the purpose of an escape ramp on a mountain grade?
Show answer
Answer C: To stop a runaway vehicle without injuring the driver
Escape ramps use soft material or a steep upgrade to bring a vehicle with failed brakes to a controlled stop.
-
28. At a rest area you find that the load has shifted although the straps still feel tight. What should you do?
Show answer
Answer C: Correct the load before driving on, since a shifted load is no longer secure
Movement means the securement has already failed once, and a load that has shifted can shift again, so it is put right before the vehicle moves.
-
29. Which of these is NOT on the federal list of parts and accessories the driver must be satisfied are in good working order before driving?
Show answer
Answer D: The seat cushion upholstery
The federal pre-trip rule names brakes, steering, lights and reflectors, tires, horn, wipers, mirrors, coupling devices, wheels and rims, and emergency equipment; seat upholstery is not on that list.
-
30. Why must cargo also be held down against vertical movement and not only against sliding?
Show answer
Answer D: Because a load that bounces can jump the blocking and slacken its own tiedowns
Rough road makes an unrestrained article lift; every bounce lets it move a little and works the tiedowns loose until nothing is holding it.
-
31. Where should a driver expect fog to form first?
Show answer
Answer D: In low ground, near water and in valleys
Cool moist air settles in low places, so fog patches appear in hollows, river valleys and near lakes before they appear anywhere else.
-
32. When should the horn of a commercial vehicle be used?
Show answer
Answer C: Only when it is needed to avoid a crash
An air horn is loud enough to startle other road users, so it is a warning device rather than a way to comment on other drivers.
-
33. How do you get more engine braking from an automatic transmission on a downgrade?
Show answer
Answer B: Select a lower range before starting down
Locking the transmission into a lower range keeps engine speed high enough to hold the vehicle back and spares the service brakes.
-
34. What does mountain driving demand that flat country driving does not?
Show answer
Answer D: Lower gears and constant allowance for gravity
In the mountains gravity works for you on the climb and against you on the descent, so gear selection and speed control matter far more than on level road.
-
35. How does a driver keep a vehicle with a manual transmission from rolling back when starting on an upgrade?
Show answer
Answer D: Partly engage the clutch before the right foot leaves the brake, or hold the vehicle with the parking brake until the engine pulls
Something has to hold the vehicle during the instant the foot moves from the brake to the accelerator, and that is either the clutch at its engagement point or the parking brake.
-
36. What should be checked about the power steering system in the engine compartment?
Show answer
Answer D: That the fluid level is correct and the hoses and pump are not leaking
Losing power steering fluid means losing steering assistance, which can happen suddenly and makes a heavy vehicle very hard to turn.
-
37. Which shock absorber condition is a defect?
Show answer
Answer C: A shock that is leaking, broken or disconnected at either mounting
A shock that has lost its fluid or its mounting no longer damps the suspension, so the wheel bounces and loses contact with the road.
-
38. While double clutching, what goes wrong if you take too long between the two clutch movements?
Show answer
Answer A: Engine speed falls too far and the gear becomes hard or impossible to engage
Double clutching only works while engine speed and road speed still match; a slow shift lets rpm drop away and the gear will not go in.
-
39. At the end of the day you find no defects on a property carrying vehicle. What does the federal rule require?
Show answer
Answer B: No written report is required, although the carrier may still ask for one
For property carrying vehicles the report is required only when a defect or deficiency is found or reported, although a carrier may impose a stricter policy.
-
40. How is free play in the steering wheel measured during the inspection?
Show answer
Answer B: By turning the wheel until the front wheels just start to move and noting the movement
Play is the movement at the rim that produces no movement at the road wheels, so it is measured by turning until the wheels first respond.
-
41. A straight truck has a long body behind the rear axle. What happens to that overhang in a sharp left turn?
Show answer
Answer D: It swings out to the right and can strike a vehicle or an object on that side
Body that hangs behind the rear axle swings the opposite way to the turn, so the tail of the truck sweeps out into the next lane or over the curb.
-
42. Why do cracked spring hangers or badly worn shackles matter?
Show answer
Answer A: They allow the axle to shift out of its correct position under the vehicle
Hangers and shackles hold the spring, and therefore the axle, in place, so when they fail the axle can move and the vehicle may become uncontrollable.
-
43. The paperwork shows a weight, but the load looks heavier than you expected. What should you do?
Show answer
Answer C: Weigh the vehicle, since you are the one answerable for driving it overweight
The driver is the one who can be cited for an overweight vehicle, so a doubtful weight is settled on a scale before the trip continues.
-
44. You are the first to arrive at a crash. What is the correct order of actions?
Show answer
Answer C: Protect the area, notify the authorities, care for the injured
Preventing a second crash comes first, because an unprotected scene puts the injured and the helpers in more danger than the original collision.
-
45. What is the coupling device weight rating on a vehicle?
Show answer
Answer A: The most weight that the coupling on the vehicle is rated to pull
The coupling device rating is a limit on how much weight the coupling may tow, and it is one of the ratings that has to be respected when a combination is loaded.
-
46. You drive a 40 foot straight truck at 50 miles per hour in good conditions. What following distance does the rule of thumb call for?
Show answer
Answer A: 5 seconds
One second for every 10 feet of vehicle length gives 4 seconds, and one extra second is added for speeds above 40 miles per hour.
-
47. Why does extra weight make a long downgrade more dangerous even when the brakes are in good order?
Show answer
Answer B: Gravity adds to the momentum and the brakes heat up faster
The heavier the vehicle, the more energy the brakes must turn into heat, and heat is exactly what makes brakes fade on a long descent.
-
48. When must a driver first inspect the cargo and its securement devices?
Show answer
Answer C: Before starting the trip, as part of the pre-trip inspection
Cargo is part of the pre-trip inspection; the later checks within 50 miles and every three hours or 150 miles come on top of that first inspection.
-
49. Where should a trailer be dropped, and what else does the driver do before pulling out from under it?
Show answer
Answer C: On solid level ground, with the trailer wheels chocked if it may roll
A dropped trailer must sit on ground that will carry the landing gear without sinking, and chocks stop it rolling once the tractor and its air supply are gone.
-
50. In dense city traffic you cannot see 12 seconds ahead because other vehicles block the view. What is the best response?
Show answer
Answer A: Slow down and open up more space in front of you
When you cannot see far enough ahead, extra following distance buys back the reaction time that the blocked view has taken away.