Manitoba Commercial study guide: key rules on all 18 topics

Free Manitoba Commercial study guide: 388 key points from the MPI Professional Driver's Manual in plain words, organised by topic, each topic linked to its practice questions.

By the Canada Exam Prep Editorial Team · Updated October 17, 2026

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This study guide collects our notes on every topic of the Manitoba Commercial Knowledge Tests (Class 1–4 and Air Brake) on one page: 388 short points in our own words, grouped by topic and by handbook section. Read it from top to bottom before your first practice test, or jump to a topic from the list below.

Each topic ends with a link to its practice questions, so you can check what you just read straight away, and a link to the official chapter for the full wording. The notes summarise the MPI Professional Driver's Manual from the Manitoba Public Insurance (MPI); they do not replace it, and where our notes and the official source differ, the official source wins.

Study these notes as flashcards →

Licence classes, testing and medical rules

What Class 1 to 4 licences allow in Manitoba, minimum age and Class 5 stage needed, Authorized Instruction and supervising drivers, MELT, knowledge and road test rules, medical and vision standards, US commercial driving and the air brake endorsement.

Practise Licence classes, testing and medical rules questions Flashcards Official chapter

The class licence system (fold-out) and Basic licensing requirements (pp. 3–4)

Class 1: semi-trailer trucks, plus everything in Classes 2–5; minimum age 18.
Class 2: buses seating over 24 passengers and school buses seating over 36, while carrying passengers; includes Classes 3–5.
Class 3: trucks with more than two axles; combinations with such a truck (not semi-trailers); a two-axle truck, or a Class 5 vehicle other than a truck, towing a unit registered over 4,540 kg; includes Classes 4 and 5.
Class 4: ambulances and other emergency vehicles, buses seating 10 to 24 and school buses seating 10 to 36 while carrying passengers; includes Class 5. Some municipalities require Class 4 for vehicles for hire.
A bus is any vehicle designed to carry 11 or more people including the driver that is not used only for personal transportation.
Authorized Instruction in Classes 2–4 needs at least a Class 5I or 5A licence; Class 1 needs at least a Class 5F (Full) licence. Road tests for Classes 1–4 need a Class 5F licence.
The supervising driver must have held a full Class 5 for at least three years, two of them in the class being learned, sit nearest the driver, have under .05 blood alcohol and pass any drug screening.
Class 1 applicants must show they completed an approved MELT course before booking the road test; practice hours as a 1A learner do not count toward MELT.
You must be tested for a class if you were never licensed in it, have not held a Manitoba licence in the past four years, or hold a non-exchangeable licence.

Test appointments and key points (p. 5)

Tests are by appointment through an Autopac agent and can be booked up to eight weeks ahead; weekdays, with Saturday appointments in Winnipeg.
Fees change: the manual lists a $10 knowledge test, but MPI's testing page (checked October 2026) lists $12 per knowledge test and road tests of $50 (Class 1, 2 or 3), $40 (Class 4) and $35 (air brake practical).
Knowledge tests for Class 1 and air brake are offered in English, French or Punjabi; Class 2, 3, 4 and school bus tests in English and French.
Knowledge tests have a 30-minute limit, are not open book, and phones and electronic devices are not allowed.
Only one knowledge or road test of the same class per day; Class 1–4, air brake and school bus knowledge tests can be repeated the next working day.

Ch. 1 Class 1 to Class 4 requirements (pp. 8–10)

A Medical Examination Report is mandatory for Classes 1–4; you may write the knowledge test before it is approved, but it must be approved before Authorized Instruction is issued.
The medical report is valid for six months, and Authorized Instruction must be obtained within that time.
Vision: at least 6/9 with both eyes, the worse eye at least 6/30, and a 150° visual field.
Medical reports are renewed every five years to age 45, every three years to age 64 and every year from 65.
The knowledge tests for Classes 1–4 are based on the Professional Driver's Manual and are not open book.
Class 1 road tests must be done in a manual-transmission vehicle, with a Daily Vehicle Inspection Report from the past 24 hours.
A Manitoba Class 1–4 licence is accepted as a commercial licence in the US; drivers with certain medical conditions get a Code W restriction. US rules require age 21 and a medical card.
Any vehicle with air brakes needs an air brake endorsement: a knowledge test plus a practical test (A endorsement); adjusting manual slack adjusters is the separate S endorsement.
The air brake practical demonstration is part of every Class 1 road test.

Impairment, fatigue and safety equipment

Impaired driving sanctions, carbon monoxide, emotions, fatigue and sleep debt, hours of service, airbags and seatbelts, distractions, warning reflectors, fire fighting and extinguishers.

Practise Impairment, fatigue and safety equipment questions Flashcards Official chapter

Ch. 2 Driving while impaired (pp. 14–15)

Impaired drivers caused 40% of traffic deaths in Manitoba in 2018; you can be charged with impaired driving at any blood alcohol level.
Only time removes alcohol; coffee, food or a cold shower do not.
In Manitoba, alcohol carried in a commercial vehicle must be out of the driver's reach with the seal unbroken; in the US it is banned unless part of a manifested load.
Prescription drugs can impair even at the prescribed dose; carry them in their original containers.
Drivers suspected of drug impairment can get an immediate 24-hour roadside suspension.
BAC of .05 to .079, a warn on a screening device, or a failed drug or coordination test brings a Tiered Administrative Licence Suspension: 72 hours first time (seven days with a child under 16 aboard), 15 days second, 30 days third, 60 days after that, within 10 years.
A BAC of .08 or more, a fail, refusal, THC over 5 ng or any illegal drug brings a three-month Administrative Licence Suspension, impoundment and an Impaired Driver Assessment.
Driving while suspended means impoundment for at least 30 days, even if someone else owns the vehicle.

Ch. 2 Safety considerations (pp. 16–17)

Carbon monoxide is odourless, colourless and tasteless; check the exhaust and get fresh air if dizzy or drowsy.
Fatigue is a factor in 30–40% of heavy truck fatalities; drivers usually do not notice it coming.
Most people need six to eight hours of sleep; missed sleep builds a sleep debt that must be repaid.
Micro sleep: the brain tunes out for seconds; highway hypnosis: inattention from dull terrain.
If you are very tired, pull off and sleep before you fall asleep at the wheel.
Hours of service rules exist to manage fatigue; contact the Motor Carrier Branch for details.
Sit at least 25 cm from an airbag in the steering wheel; keep the area in front of airbags clear.
All occupants must wear the full seatbelt; children need a car seat until at least 145 cm, 36 kg or age nine.
Using hand-held electronic devices while driving is illegal in Manitoba.

Ch. 2 Safety equipment and vehicle fires (pp. 18–19)

Passenger vehicles, vehicles carrying flammable goods (loaded or not) and pilot vehicles must carry fire extinguishers.
All buses and trucks registered at 4,500 kg or more must carry three reflectorized warning devices.
On a divided highway, place them 3 m, 30 m and 60 m behind the vehicle.
On an undivided highway, the manual lists one device 3 m and one 30 m from the front of the vehicle, and one 30 m behind it.
Fire: do not risk your life; separate tractor and trailer only if safe; fight with the wind at your back; disconnect the battery for electrical fires; open the hood only slightly.
Water spreads fuel, oil and grease fires; use an extinguisher, sand or dirt.
B.C. extinguishers handle grease, oil, fuel and electrical fires; A.B.C. also handles paper and cloth; do not use CO2 in an enclosed space.
Never start a vehicle with a fuel leak, shut off the engine to refuel, ground the nozzle, and do not start propane heaters with trailer van doors closed.
Let soft or flat tires cool before moving; replace the tire first if you must move.

Fuel-smart driving, night driving and vehicle controls

Fuel efficiency habits, starting and warming up, night driving distances and dimming, hand position, clutch and double-clutching, engine rpm and gear changes, shifting before hills, curves and railway crossings, lane use.

Practise Fuel-smart driving, night driving and vehicle controls questions Flashcards Official chapter

Ch. 2 Fuel efficiency (pp. 12–14)

Road transportation produces nearly 30% of Canada's greenhouse gas emissions.
Aim for 80–90% payload capacity rather than 60%; summer fuel above 0 °C can improve economy up to 3%.
Cutting aerodynamic drag 10% reduces fuel use about 5%; each 10 psi of under-inflation adds about 1% fuel use.
Snow-covered roads can raise fuel use 15–20%.
Start with zero throttle and do not pump it; warm up three to five minutes, or seven to ten below 0 °C.
Check gauges, tires and cargo every three hours during a trip.
Every 10 km/h over 90 km/h uses about 10% more fuel.
Progressive shifting: shift between 1,400 and 1,600 rpm, before maximum governed rpm.
An idling class 8 truck burns up to four litres an hour at 900 rpm.
Keep a following distance of at least four seconds; at 70 km/h stopping takes about 90 m.

Ch. 2 Lighting and night driving (pp. 20–21)

Daytime running lights are required on vehicles built on or after December 1, 1989.
Low beams light about 30 m ahead and high beams about 110 m; never outdrive your headlights.
Dim your lights at least 450 m from oncoming vehicles and 60 m when following.
To reduce glare, look toward the right edge of the road.
Keep interior lights off at night; use low beams in fog, under street lights and when following closely.

Ch. 2 Vehicle operation (pp. 22–24)

Hold the wheel at nine and three o'clock; never palm the wheel or steer with one finger.
A big turn may take up to eight turns of the steering wheel.
Do not ride or slip the clutch to hold on a hill; it overheats and wears out.
The clutch brake is used only when stopped; do not push the clutch to the floor while moving.
Double-clutching: clutch in, neutral, clutch out, match engine rpm, clutch in, select gear.
Engines are usually efficient between 1,200 and 1,800 rpm; the tachometer is the most accurate way to time shifts.
An automatic can be shifted down for engine braking on a hill.
Select your gear before starting down a hill, before a curve and before railway tracks; do not shift on the tracks.
In cities large vehicles should use the curb lane; slower vehicles must use the right lane on multi-lane highways.
A stale green light has been green for a while and will probably change soon.

Speed, following distance and braking

Speed, weight and stopping force, the danger zone, the four-second rule and length-based count, traffic tempo, tailgaters, the 90 m rule, slow-moving vehicles, snubbing and control speed, retarders, ABS and runaway lanes.

Practise Speed, following distance and braking questions Flashcards Official chapter

Ch. 2 Speed, weight and the danger zone (pp. 26–27)

Doubling weight needs double the braking force; doubling speed needs four times; doubling both needs eight times.
The danger zone is the area ahead in which you cannot stop; it grows with speed and on rain, snow, ice or gravel.
Slowing down shrinks the danger zone; so does covering the brake when a hazard may develop.

Ch. 2 Following distance and traffic tempo (pp. 28–30)

Ambulances and vans: at least a four-second following distance.
Buses, trucks and truck-trailers: round the length to the nearest metre and divide by three, but never use less than four seconds.
Lengthen the count on rain, snow or ice.
Driving faster than traffic tempo removes your stopping space and adds lane changes and fatigue; driving slower invites tailgating and unsafe passing.
Large-vehicle drivers depend on outside mirrors; help a tailgater pass and stop gradually.
Outside a restricted speed area, regulated vehicles, trucks, highway buses and vehicles towing equipment must not follow within 90 m of each other.
On an upgrade with a passing lane, slower vehicles must use the right lane.
The slow-moving vehicle sign may be shown only by vehicles travelling 40 km/h or less.

Ch. 2 Braking (pp. 31–33)

A level stop normally takes one brake application, eased off at the end.
On ice without ABS, lightly release or pump the brakes so the wheels do not lock.
Choose a lower gear before a steep downgrade and keep the vehicle in gear; control speed is the downhill speed with rpm just below governed speed.
Snubbing: brake to slow about 8 km/h in about three seconds, then release ("8 in 3"); do not let speed rise more than 8 km/h above control speed before snubbing.
Where signs require a brake check, you must stop; record the stop in the log book.
Engine retarders are used along with snubbing; avoid unnecessary use in cities; choose the gear before the grade; retarders may not be used on road tests.
With ABS, brake normally and keep steady pressure; do not pump; ABS cycles up to five times a second.
Balanced braking: the foot valve applies trailer brakes at the same pressure as the tractor; the hand valve applies them alone.
Over-braking in curves or on ice without ABS can cause a jackknife or skid.
Runaway lanes are soft gravel, ash or wood-chip lanes for trucks with failed brakes: foot off the accelerator, hold the wheel tightly, steer straight up the lane.
Rising application pressure with each snub on a long grade (for example 9, 15, 20, 30 psi) is a warning of brake fade; act at once.

Tires, wheels, passing and intersections

Tread depth limits, retreads, tire pressure and heat, wheel fasteners and failures, passing and being passed, lane changes, curves and intersection rules for large vehicles.

Practise Tires, wheels, passing and intersections questions Flashcards Official chapter

Ch. 2 Tires, wheels and fasteners (pp. 34–35)

Bald or damaged tires may not be used; check tires before each trip with a gauge.
Buses, trucks and tractors 4,500 kg GVWR or more: at least 3 mm tread on front steering tires and 2 mm on rear tires; under 4,500 kg: 1.6 mm on all tires.
Retreaded tires may not be used on steering axles; do not mix radial and non-radial tires or sizes on an axle.
Over-inflation wears the centre; under-inflation wears the edges and raises the hydroplaning risk.
Never bleed air from a warm tire; check and adjust pressure cold.
Lug nuts loosen as rims heat and cool; retorque after a rim is reinstalled (about 210–260 ft-lb on cast spoke wheels, 450–500 ft-lb on disc wheels).
A loose lug nut found during a pre-trip means a qualified technician must inspect the unit.
Whole-wheel separations usually come from bearing failure; warning signs are oil leaks and very hot hubs.
A separated wheel travels faster than the vehicle; a truck tire weighs about 181 kg.

Ch. 2 Passing, lane changes, curves (pp. 36–37)

Do not stay in the passing lane longer than needed; a small speed difference causes bunching.
Turbulence is felt beside the saddle tanks and near the rear of the trailer.
Do not wave other drivers past; when they pass, slow down to help them.
Lane change: mirrors, signal, mirrors again including convex, check the blind spot, keep signalling until fully in the lane.
Vehicles that rely only on mirrors should change one lane at a time; never change lanes in intersections or over solid lines.
Braking in a curve adds to centrifugal force and can cause a rollover, skid or jackknife; slow down before the curve and apply slight power in it.

Ch. 2 Intersections (p. 38)

More collisions happen at intersections than anywhere else.
Never enter a limited-view intersection faster than you can stop; do not assume right of way.
A flashing or steady "don't walk" signal warns that a stale green will change.
At an uncontrolled intersection both drivers slow down and the vehicle on the left yields to the vehicle on the right.
Do not use your size to take the right of way.

Backing, parking and railway crossings

Backing rules and guides, leaving alleys and lanes, securing an unattended vehicle, and Manitoba railway crossing distances, prohibitions and when you may cross with lights flashing.

Practise Backing, parking and railway crossings questions Flashcards Official chapter

Ch. 2 Backing (pp. 39–41)

The driver is always responsible for any incident while backing; most backing collisions come from failing to look.
Avoid unnecessary backing and plan to minimize it.
A guide should stand at the rear with a clear view of the path and stay visible in the driver's mirror.
Plan the approach so you see the area you will back into; back to the view side rather than the blind side.
Back out of traffic, not into it.
With no guide: get out and check, look above, below and all around, then sound the horn and back very slowly using both mirrors.
Sound the horn for each vehicle length travelled; make a series of short backing moves rather than one long one.

Ch. 2 Alleys and parked vehicles (p. 42)

Leaving a parking lot, alley, private road or side road: stop before the sidewalk area, yield to pedestrians, then stop again before the road and yield to vehicles.
Before leaving a vehicle: set the parking brake, stop the engine, use the recommended gear, two-speed axle in low range, remove the key.
On a hill, turn the wheels so the vehicle would roll off the road; with a combination, so the trailer would roll off the road.
Never use the trailer hand valve alone to hold an unattended tractor-trailer.

Ch. 2 Railway crossings (pp. 43–44)

When stopping at a crossing, stay at least 5 m from the nearest rail in a restricted speed area and at least 15 m outside one.
A restricted speed area means Winnipeg, an urban municipality, a local urban district or another designated area.
Trains always have the right of way; most drivers misjudge their speed.
With more than one track, make sure no second train is coming after the first passes.
Half of nighttime crossing collisions are vehicles hitting trains.
Do not start across unless the rear of your vehicle will clear; if traffic is backed up, wait at least 5 m from the crossing.
Buses, school buses and vehicles carrying flammable materials must stop at crossings.
Illegal: crossing when signals are on (with exceptions), shifting gears on the tracks outside a restricted speed area, going around a gate, entering without room on the far side, parking within 30 m of the nearest rail.
With lights flashing you may cross only after a full stop, where there are no gates, inside a restricted speed area, with the train stopped or far away, and when safe.
Never pass a lowered gate unless directed by a flag person or authority.
If you damage a crossing or track, notify the railway right away.

Weather, winter roads, skids and jackknifing

Ice and snow, reduced visibility, black ice, Manitoba winter and ice roads, strong winds, hydroplaning, wet brakes, the causes of skids, skid recovery and jackknifing.

Practise Weather, winter roads, skids and jackknifing questions Flashcards Official chapter

Ch. 2 Adverse weather and reduced visibility (p. 45)

On ice or snow: start slowly and test steering and brakes, lower speed, use chains if needed, brake lightly, avoid jerky steering, keep windows and lights clean, ventilate the cab.
A manual front brake limiting valve can reduce front braking to improve steering on slippery roads.
In fog, heavy rain or snow use low beams; if visibility is too poor, use hazard lights and pull off the road until it improves.

Ch. 2 Winter and winter road driving (pp. 46–47)

Bridges and overpasses can form black ice near freezing or in extreme cold.
Smaller vehicles may follow a large vehicle through a storm; allow for them when braking.
On ice roads, the recommended speed for vehicles of 7 tonnes GVWR or more is 15 km/h; faster can create an ice wave and break the ice.
Do not use a winter road before it officially opens.
Drive near the centre of ice roads, away from the snow banks at the sides.
Never stop or park trucks on an ice road; load and unload only on land.
Trucks travelling the same way on an ice road should be staggered one kilometre apart.
Do not cross a pressure-ridge ramp bridge whose planks have lifted or twisted.
First-time winter road drivers should go with an experienced driver; a 24-hour log book is still required.

Ch. 2 Wind, hydroplaning and wet brakes (p. 48)

In strong wind: slow down, grip the wheel firmly, correct gently, avoid passing, increase following distance.
Below about 50 km/h tires normally cut through water; at about 70 km/h and above they can ride on a wedge of water.
Worn or under-inflated tires or deep water can cause hydroplaning even below 50 km/h.
Drive through water with a light drag on the brakes, then apply them lightly to dry them.

Ch. 2 Skids and jackknifing (pp. 49–51)

Most skids come from driving too fast for conditions; causes are overbraking, overaccelerating and oversteering.
Using the trailer brakes alone on a tractor-trailer can cause a jackknife.
Correct the cause first: release the brake for a braking skid, release the accelerator for a power skid, push in the clutch if too low a gear caused it.
Steer in the direction the rear end is skidding, then counter-steer slightly as it straightens.
If a trailer starts to skid while braking, release pedal pressure; avoid using the hand valve by itself.
A jackknife is when the tractor reaches an angle of 90° or less to the trailer, usually after the drive wheels lose traction.

Trip inspections and road test vehicle rules

Who must do a daily trip inspection, what the report contains, major and minor defects, the road test inspection and vehicle requirements, tread, mud flap and reflective tape rules, hydraulic brake checks, in-service, post-trip and pre-hill inspections.

Practise Trip inspections and road test vehicle rules questions Flashcards Official chapter

Ch. 5 Vehicle condition (p. 92)

A commercial motor vehicle is a regulated vehicle of 4,500 kg GVWR or more, a bus seating 11 or more used for gain, or a school bus.
A trip inspection is required once every 24 hours the vehicle is in service, under the Commercial Vehicle Trip Inspection Regulation (MR 95/2008).
The report includes plate or unit number, odometer, carrier, date and time, location, the inspector's printed name, and the height and width of vehicle and load.
Report any suspected safety defect to the carrier; a major defect must be reported immediately and the vehicle may not be operated.
Drivers must carry a current trip inspection report for the vehicle and any trailer.

Ch. 5 Trip inspection testing and road test reminders (p. 92)

Class 1, 2, 3 (including pickups towing over 4,540 kg) and Class 4 bus road tests include a trip inspection of the vehicle you supply.
The Class 2, 3 and 4 inspection should take no more than 20 minutes; the hydraulic brake check no more than 5.
Class 1 applicants inspect specific components and also complete a coupling exercise.
An incomplete inspection, coupling or brake inspection ends the road test as a failure.
Trailers must be registered over 4,540 kg; trucks 4,500 kg or more need a valid inspection sticker and three flares or reflectors.
Mud flaps are required, no more than 350 mm from the ground.
Reflective tape must cover at least 50% of the sides and 100% of the back.
Placarded vehicles, or vehicles carrying flammable fuel containers over 500 L, cannot be used for a road test.

Ch. 5 Class 1 and Class 2–4 inspection items (pp. 93–104)

Major air brake defects include pushrod stroke over the limit, excessive air loss, a faulty low air warning, and parking or emergency brakes that do not work.
Coupling check: apply trailer brakes, release tractor brakes and rock gently forward and back; look under the trailer to see the jaws closed.
Major tire defects: flat tire, tread below the limit, tire touching another tire, "not for highway use" marking, exposed cords.
A fuel leak that drips is a major defect; a missing fuel cap is minor.
Failure of both rearmost brake lamps, or of one rearmost turn signal, is a major defect.
An exhaust leak into the cab is a major defect.
Windshield chips or stars of 12.7 mm or more in the wiper area must be reported.
Wipers must clear about 75% of the windshield.
Hydraulic brakes: with steady moderate pressure for one minute, the pedal must not sink more than 65%.

Ch. 5 In-service, post-trip and pre-hill inspections (p. 107)

In-service checks: wheel nuts, tires, hub and drum heat, brakes, couplings, load, drive line and oil leaks, lights and windshield; record them in the log book.
Post-trip defects are added to that day's trip inspection report.
Where signs require it, stop before a steep hill and check compressor pressure, pushrod travel, air leaks, gladhands and lines, drum heat and emergency valve; hydraulic systems check pedal reserve, vacuum booster, drums and leaks.

Turning, backing and coupling (Class 1 and 3)

Off-tracking, right and left turns with button hook, extended approach and lane straddling, backing a tractor-trailer, the Class 1 straight line backing test, draw-bar rules, and Manitoba's coupling and uncoupling steps.

Practise Turning, backing and coupling (Class 1 and 3) questions Flashcards Official chapter

Ch. 3 Types of vehicles and turning (pp. 54–56)

Class 1 covers highway trains, tractor tridems and tractor-trailers; Class 3 covers straight trucks, tractors without a semi-trailer and trucks towing over 4,540 kg.
Class 1 and 3 drivers must also know Section 4 (buses).
Turning sharpness depends on the front-wheel turning radius and the off-track of the rear wheels; the longer the wheelbase, the more off-track.
On a curve right, keep the front wheels near the centre line; on a curve left, near the right edge.
Before turning: adjust speed so you need not brake in the turn, check mirrors and signal, pick a gear that lets you finish without shifting.

Ch. 3 Right and left turns (pp. 57–61)

On right turns the rear wheels must stay on the pavement within about 1.5 m of the curb.
Finish a right turn in the curb lane; if a vehicle is parked within 30 m of the corner in that lane, you may use the next lane if it does not interfere.
Signal about 30 m before the intersection in towns, 150 m outside cities, towns or villages.
Button hook: used when the only room is inside the intersection; steer left near the corner, then right quickly when the trailer pulls away from the curb.
Extended approach: drive well into the intersection before turning; used when the street being entered is wide.
Lane straddling is a last resort, because traffic may try to pass on the inside.
The critical point is when the tractor is at its sharpest angle to the trailer, because mirror vision is limited.
If two lanes may turn right, use the left-most one; if two lanes may turn left, use the right-most one.
On left turns the trailer must stay in the path a car would take, and the rear wheels should stay left of the centre of the intersection.

Ch. 3 Backing and the straight-line backing test (p. 62)

To back a tractor-trailer, turn the steering opposite to where you want the trailer to go (hand at the bottom of the wheel moves the way the trailer should go).
Follow the trailer with the tractor or it will jackknife; the backing path is an S-curve.
Class 1 road test: back straight between two lines of cones 3.7 m apart and 18.5 m long, in five minutes, with at most three pull-ups, stopping within one metre of the last cones.

Ch. 3 Connecting vehicles, coupling and uncoupling (pp. 63–64)

Coupling devices must be strong enough and fastened to main frame parts; a trailer under 900 kg GVWR may couple to a strong part of the frame.
Except for pole trailers, the draw-bar may not exceed 5 m.
Any coupling other than a fifth wheel needs an auxiliary safety chain or cable of equal strength.
Coupling: inspect the tractor (jaws open, release handle unlocked, plate tilted down and greased); back slowly and stop with the fifth wheel ahead of the trailer and the rear axle under its front.
Set the trailer height so it contacts the lower half of the fifth wheel's face.
Engage the fifth wheel, then do a tug test in the lowest forward gear; get out and check there is no gap and the lock is closed.
Connect lines, fully raise the landing gear, supply air with the trailer supply valve and listen for leaks at each gladhand; remove chocks and test the brakes.
Uncoupling: park straight on ground that will hold the trailer, apply both sets of parking brakes, chock if needed.
Lower the landing gear until it touches the ground or is less than 2 cm above it, without raising the trailer.
Unlock the fifth wheel and drive slowly forward until the fifth wheel clears but the frame is still under the trailer; check the trailer is stable, then drive clear.

Dimensions, weights and loads (Class 1 and 3)

Height, width and length limits, permits, utility approvals, escort and pilot vehicles, weight rules and spring restrictions, weigh stations, load distribution, securement, projections, night oversize lights and farm equipment.

Practise Dimensions, weights and loads (Class 1 and 3) questions Flashcards Official chapter

Ch. 3 Vehicle and load dimensions (pp. 65–69)

Oversize or overweight loads need permits; posted size and weight signs must be obeyed whatever the permit says.
In Manitoba the driver or company is charged if their vehicle or load damages a highway or structure.
Maximum height is 4.15 m without a permit; know your height at all times; snow can reduce clearances.
Over 4.6 m the permit must also be approved by Bell MTS, and over 5.2 m by Manitoba Hydro.
Owner and operator are jointly responsible for damage to an underpass when height warnings are ignored.
Maximum width is 2.6 m; loose hay, straw or fodder may be loaded to 3.7 m.
Mirrors and clearance lights may extend 20 cm on each side; load securement devices 10 cm.
Loads wider than 4.6 m need escort vehicles front and rear; wide load signs only when actually carrying a wide load.
Legal lengths: single vehicle 12.5 m; truck or car pulling a trailer 21.5 m; tractor-trailer with load 23 m.
Over 30 m long, a pilot vehicle must follow.
Pilot vehicles have a yellow flashing light and an illuminated WIDE LOAD or D sign, and stay 100–500 m from the load.
It is illegal to exceed a tire's, axle's, suspension's, brake's or trailer's rated capacity.
Spring road restrictions limit weights while thawing roads are soft; fines are based on the excess weight.
Trucks registered at 4,500 kg or more must report to weigh stations when signs or a peace officer direct.

Ch. 3 About loads and loading (pp. 70–74)

Poor weight distribution can overload an axle or tires and bend the frame even under the total capacity.
A heavy concentrated load goes just ahead of the rear axles on its long side; never against the cab or on one side.
Trucks carry about 90% of payload on the rear tires and 10% on the front; a trailer's load is shared equally by its rear tires and the fifth wheel.
Never load at the tailgate; a tractor-trailer's central loading point is about the middle of the trailer.
Secure the whole load and check tie-downs often; an unsecured load shifts forward when braking.
Cover wood chips, paper, refuse, gravel and stones with a tarp; clean debris off side ledges before leaving.
The Cargo Securement Regulation adopts National Safety Code Standard 10.
A rear overhang of more than one metre needs a red flag at least 30 cm square, visible from 60 m, and a red light or reflector at night.
A load may not project more than one metre beyond the front bumper without a permit.
Oversize night travel needs green or amber lamps in front, red lamps at the rear and lamps at the widest points.
Farm equipment travels at 40 km/h or less and may take more than half the road.
A Class 5I or higher licence is needed to drive heavy and agricultural equipment on provincial highways and urban roads.
The tailgate must be closed and fastened unless carrying an article too long to fit otherwise.

Dangerous goods, special loads, highway trains and tow trucks

Dangerous goods duties, classes and placards, documents and spill reporting, livestock, hanging meat, bulk and tank loads, highway trains and rear amplification, and tow truck rules.

Practise Dangerous goods, special loads, highway trains and tow trucks questions Flashcards Official chapter

Ch. 3 Transporting dangerous goods (pp. 75–79)

Report any release, reportable occurrence, loss or theft of certain goods, or delayed explosives.
Anyone handling, offering or transporting dangerous goods must be trained or directly supervised; training certificates are renewed every 36 months.
The consignor supplies placards with the UN/NA number and the shipping document; the carrier displays and replaces safety marks, keeps documents two years and refuses non-compliant shipments.
Classification is the job of the manufacturer, or the generator for waste, before shipping.
Nine classes, e.g. Class 2.1 flammable gas (red), 2.2 non-flammable gas (green), 3 flammable liquids, 8 corrosives, 9 miscellaneous.
Labels go on small containers; placards on containers over 454 L and transport units; gasoline is UN 1203.
With the driver in the cab, the shipping document is within reach or in the door pocket; when out of the cab, on the seat or in the door pocket.
After unloading, the carrier's copy is marked "residue last contained" until the unit is cleaned or purged.
Placarded vehicles must stop at uncontrolled railway crossings.
Report spills to police or fire and, in Manitoba, the conservation department; CANUTEC is 613-996-6666 or *666 on a cellphone.

Ch. 3 Special loads (pp. 80–81)

Livestock haulers keep the vehicle clean and not overcrowded and use partitions to separate different species, kinds or sizes.
Animals shift as they balance, which can change the centre of gravity in curves.
Hanging meat has a high centre of gravity; take corners, speed changes and braking gently.
Bulk loads like sand or wood chips usually need a tarp; snow, earth or mud need not be tarped if none falls off.
Liquid surges forward and back in a tank when slowing; baffles reduce fore-and-aft surge but not side-to-side.
Partly filled tanks are hardest to control in curves; most tanks are considered full at 70% because liquids expand when heated; heavy liquids may only partly fill a tank.
Dry bulk tanks and hoppers have a high centre of gravity.

Ch. 3 Highway trains and tow trucks (p. 82)

A highway train is a tractor with more than one trailer, possibly with a converter dolly.
Avoid abrupt steering; rear amplification roughly doubles the tractor's sideways acceleration at the last trailer and can roll it.
A jackknife over 15° is almost impossible to stabilize, and the critical point can come in about a second and a half.
Hitch the heaviest trailer to the tractor; spread each trailer's load evenly and keep the centre of gravity low.
A tow truck needs Class 3 if it has more than two axles or tows over 4,540 kg, otherwise Class 5.
Tow trucks need an amber flashing light visible at 150 m, used only while towing or as a hazard warning at a collision.
The distance between a tow truck and a towed disabled vehicle must not exceed 5 m.

Buses, school buses and emergency vehicles (Class 2 and 4)

Which licence class each bus and school bus needs, school bus stops at railway crossings, emergency vehicle exemptions and duties, and the extra trip inspection items for buses.

Practise Buses, school buses and emergency vehicles (Class 2 and 4) questions Flashcards Official chapter

Ch. 4 Buses and school buses (p. 86)

Buses seating over 24 occupants including the driver need Class 2 or higher while carrying passengers; 11 to 24 occupants need Class 4 or higher.
Passenger vehicles used for personal transportation need only Class 5.
School buses seating over 36 occupants including the driver need Class 2; 11 to 36 need Class 4 or higher.
A school bus, with or without passengers, stops at railway tracks no closer than 5 m and no farther than 15 m from the nearest track, opens the service door, looks and listens both ways, and closes the door before moving.
A school bus certificate from the Pupil Transportation Unit may be required.
Class 2 and 4 drivers should also study Section 2 and the Driver's Handbook.

Ch. 4 Emergency vehicles (p. 86)

On an emergency call, drivers may exceed speed limits and go through red lights or stop signs only while sounding a bell or siren and showing flashing red, or red and blue, lights.
They must still drive with regard for safety, considering the road, the traffic and the use being made of the vehicle.
Class 4 includes ambulances and other emergency vehicles.

Ch. 5 Bus inspection items (pp. 99–103)

Class 4 bus road tests include a trip inspection; buses must also pass the extra bus checks.
Bus checks: all interior, aisle and stairwell lights, passenger seats and handrails secure, emergency exits and buzzer working inside and out, service door control and interlock, heaters, interior condition, wheelchair lift, restraints, and loading lights and stop arm.
Bus steering lash limits depend on wheel diameter, e.g. 45 mm for wheels under 300 mm.
A first aid kit, where required, must be present with its seal intact.

Driving a bus and passenger safety (Class 2 and 4)

Bus right and left turns, leaving the curb, parked-vehicle clues, passenger safety, interior lights, defects and breakdowns, fuelling, baggage, loading passengers, the driver's vision, standing passengers and refusing passage.

Practise Driving a bus and passenger safety (Class 2 and 4) questions Flashcards Official chapter

Ch. 4 Driving a bus (pp. 87–88)

Right turns: avoid scuffing the curb with the rear wheels; for a sharp turn approach 1 to 2 m from the curb and go straight until the side street's curb line shows through the front door.
Very narrow streets may require going well into the intersection, even over the centre line, with extreme caution.
Left turns: start from the left lane about one metre from the centre line or median; go straight until the intersecting curb line shows in the front left window; finish in the left lane.
Leaving the curb: check the mirror and glance over your left shoulder; signal only when ready to leave; watch the rear overhang near poles, signs and pedestrians.
Parked-vehicle clues: wheels turned out, driver at the wheel, exhaust, brake lights, signal lights.

Ch. 4 Passenger safety (p. 88)

Safe operation comes before schedules; Class 2 and 4 drivers must also consider passenger comfort.
Know your bus's turning radius, off-track, rear overhang and width.
Preventable passenger collisions: stopping improperly at the zone, loading when unsafe, sudden stops or starts with standees, fast sharp turns, misuse of doors.
Public passenger vehicles need interior lights for the whole interior and a lamp at each entrance door; keep them clean and sanitary.
If a defect makes it unsafe or uncomfortable to continue, stop and do not continue with passengers until it is fixed; after a breakdown or collision, arrange transport for passengers right away.
Do not refuel with the engine running or near an open flame; keep the nozzle in contact and grounded.
Baggage must not block entrances or exits and must be stowed so it cannot fall on passengers.

Ch. 4 Loading and unloading passengers (p. 89)

Outside a city, stop clear of the travelled road where possible when loading or unloading.
Do not collect fares, make change or load or unload while moving; avoid unnecessary conversation.
The driver's view ahead and to both sides must not be blocked; no passenger may sit to the driver's left; a sedan may seat at most two passengers on the front seat.
No standing passenger may block the driver's vision or movements.
A person at a scheduled stop with the fare may be refused only if all seats are full, or if intoxicated, boisterous, disorderly or using profane or obscene language.
A licensed animal such as a guide dog may accompany a person with a disability.

Air brake basics and the air supply

The air brake endorsement and learner rules, how air brakes differ from hydraulic brakes, the compressor and governor, normal pressure range, supply and dual tanks, draining, air dryer, alcohol evaporator, gauges, safety valve and low-pressure warnings.

Practise Air brake basics and the air supply questions Flashcards Official chapter

Foreword: air brake endorsement (p. 1)

The air brake endorsement lets you drive air-brake vehicles in the class you are licensed for; it needs a written test and a practical test.
Adjusting manual slack adjusters needs the S endorsement; only certified technicians adjust automatic slack adjusters.
The manual slack adjustment practical can be asked for only after passing the automatic slack adjustment practical.
No endorsement is needed for farm-registered Class 3 or 5 air-brake vehicles; farmers may also drive them on dealer plates for demonstration.
After meeting the written standard you may drive air-brake vehicles as a learner, supervised by someone who has held the endorsement at least two years.
MPI's testing page says you must hold a 5L licence before writing the air brake knowledge test.

Ch. 1 Vehicle braking systems (pp. 5–6)

Brakes turn the energy of motion into heat; too much heat causes fade, failure and even tire fires.
Overheated drums expand and may no longer touch the shoes; stop, let brakes cool to the touch, then check them.
One malfunctioning brake makes all the others work harder and overheat.
Hydraulic brakes act instantly because fluid cannot be compressed; air brakes always have a split-second delay.
Drum temperature guide: about 115–125 °C normal, 215–225 °C hot, 590 °C danger.
In Manitoba, air-over-hydraulic brakes need the air brake endorsement: the knowledge test plus a regular single-unit air brake practical.
Air parking brakes alone (hydraulic service brakes, e.g. some school buses) do not need the endorsement.

Ch. 2 Air-supply subsystem (pp. 7–10)

The engine-driven compressor squeezes air into a smaller space; compressed air is stored energy.
The governor stops pumping at cut-out and restarts at cut-in; cut-out is normally 20–25 psi above cut-in.
System pressure must never be below 100 psi (cut-in) or above 145 psi (cut-out); a drop below normal cut-in means stop safely as soon as possible.
The first (supply or wet) tank collects most moisture and oil; sludge can damage seals, corrode tanks and freeze.
Many manufacturers recommend draining tanks daily; drain the supply tank first.
One-way check valves stop air flowing back into the supply tank.
Primary and secondary (dry) tanks form two circuits, so one circuit can stop the vehicle if the other fails.
An air dryer between compressor and supply tank removes moisture and purges it at cut-out; tanks must still be drained.
An alcohol evaporator adds alcohol vapour to keep moisture from freezing.
Safety valves on the supply tank and dryer normally open at 150 psi; a venting safety valve needs immediate repair.
Exhausting air is fast and carries dirt and oil; know where it exhausts and stay out of its path.
The low-pressure warning must come on before either tank drops to 55 psi (most at 60 psi or higher), with a light and possibly a buzzer; a wig wag arm may drop into view.

Service brakes and spring brakes

The brake pedal and dual circuits, brake chambers, pushrod stroke and adjustment limits, who may adjust brakes, spring brake chambers, caging, the yellow parking control, automatic spring application and DD3 chambers.

Practise Service brakes and spring brakes questions Flashcards Official chapter

Ch. 3 Service brake subsystem (pp. 11–12)

Service brakes (normal stopping) and spring brakes (parking and emergency) are separate, independently controlled systems.
Pressing the pedal harder opens its valve farther and sends higher pressure to the service brakes.
With dual circuits, if one fails the brakes on the other circuit still work; which wheels each circuit feeds depends on the maker.
A service brake chamber has a diaphragm, pushrod and return spring; air pushes the rod out and the spring returns it.
The pushrod and slack adjuster link the chamber to the brake; pushrod stroke rises noticeably as pressure rises from 10 to 80 psi.
Each chamber has a stroke limit beyond which no brake force is produced; exceeding the adjustment limit is a defect.
Only drivers with an S endorsement may re-adjust manual slack adjusters; only certified technicians may adjust automatic ones.
Almost all commercial vehicles use clamp-type chambers; front wheel-limiting valves reduce steering-axle braking.

Ch. 4 Spring brake subsystem (pp. 13–15)

Spring brakes apply when air leaves the chamber and release when air builds up; a large coil spring holds them on.
The spring section is piggy-backed on the service section; the end nearest the pushrod is the service part.
Releasing spring brakes normally takes 70–80 psi; below that they begin to apply.
Never service or repair a brake chamber; a released spring can move violently.
A technician can cage the spring with a caging bolt; a caged chamber looks different and that brake will not park or stop the vehicle — have it repaired at once.
The spring brake control valve usually has a yellow, four-sided knob: push to release, pull to apply.
An optional tractor parking-brake valve with a round blue knob releases tractor spring brakes while trailer spring brakes stay on.
When pressure falls to about 60 psi the control valve exhausts the remaining air and the knob pops out, applying the spring brakes suddenly.
Poor adjustment reduces the ability of both service and spring brakes to stop or hold.
DD3 chambers on many buses lock mechanically, have three air connections, and release by using the control valve then pressing the pedal for three to five seconds.

Trailer brake subsystem

Supply and service lines, gladhands and colour codes, cross-connected lines, the trailer hand valve, the red trailer supply valve, the tractor protection valve and system, automatic trailer spring brakes and spring or service brake priority.

Practise Trailer brake subsystem questions Flashcards Official chapter

Ch. 5 Trailer brake subsystem (pp. 16–19)

A trailer's air brakes include air tanks and automatic spring brakes; a converter dolly's system is essentially a trailer system.
Two lines join tractor and trailer: the supply (emergency) line fills the trailer tanks; the service line carries brake application pressure.
Gladhands have rubber seals and must be clean; dead-end or dummy couplers protect them when not in use.
Gladhands are usually colour-coded red for supply and blue for service, and most fit only their match.
Cross-connected lines are unsafe: spring brakes may not release, the tractor may lose air and service brakes will not work properly.
Extra connectors at the rear of a trailer for doubles usually have manual shut-off valves.
The trailer brakes apply with the pedal; a hand valve can apply them alone, and the trailer gets the higher of the two pressures.
The trailer hand valve must never be used for parking or emergency stops.
The trailer supply valve usually has a red, eight-sided knob: push in to supply air, pull out to close.
It closes automatically when supply-line pressure drops to between 20 and 45 psi, usually before the gauges show it.
In an emergency when trailer service brakes fail, closing the trailer supply valve applies the trailer spring brakes.
The tractor protection valve, controlled by the trailer supply valve, closes by spring force to keep air in the towing vehicle.
The tractor protection system prevents total air loss if the trailer breaks away or the lines separate or rupture.
Trailer spring brakes must apply automatically when supply-line pressure drops below 60 psi.
Spring brake priority fills the spring brake tank first, so a trailer can move before its service brakes have air; service brake priority fills the service tank first.

Foundation brakes, brake demands and compliance

S-cam, disc and wedge brakes, how speed and weight change stopping distance, brake heat and fade, why adjustment matters, ABS, and the law on operating vehicles with defects.

Practise Foundation brakes, brake demands and compliance questions Flashcards Official chapter

Ch. 6 Foundation brakes (pp. 20–21)

Foundation brakes are the parts at the wheels; the three types are S-cam, disc and wedge.
The S-cam drum brake is the most common: pushrod stroke turns the slack adjuster and camshaft, and the S-shaped cam spreads the shoes against the drum.
S-cam internal parts include the spider, anchor pins and springs, cam head, rollers and return spring; the exposed pushrod makes adjustment easy to check.
Disc brakes use calipers, rotors and pads; wedge brakes push a wedge between the shoes, have no exposed linkage and are self-adjusting.

Ch. 7 Demands on brakes while driving (pp. 22–24)

More weight or speed means more brake work and pressing the pedal farther.
Stopping distance rises in proportion to weight; doubling speed quadruples it; doubling both multiplies it by eight.
Air brakes have a delay of up to half a second in applying and releasing.
Repeated or severe braking raises brake temperature; keeping a safe following distance reduces harsh braking.
Brake fade means pressing harder for the same braking, and in extreme cases being unable to slow down.
Small losses from poor adjustment show only under heavy demand; the law requires adjustment to be checked at least once a day.
ABS reduces force to a wheel that is about to lock, keeping steering control, but does not shorten stopping distance; with an ABS fault, regular braking still works.

Ch. 8 Air brake compliance (p. 25)

If a vehicle does not comply with The Highway Traffic Act and regulations, the driver, operator and owner must keep it off the road; penalties range from fines to impoundment.
Drivers must report air brake defects to the operator.
Inspect on level ground, away from traffic, engine off, wheels chocked whenever you leave the seat with parking brakes released, and stay out of exhausting air.

Air brake inspections, tests and brake adjustment

Inspecting linings, chambers, drums, lines, tanks and compressors, the low air warning, build-up, governor, leak, tractor protection and spring brake tests, tug tests, draining, measuring pushrod stroke, long-stroke chambers and the S endorsement.

Practise Air brake inspections, tests and brake adjustment questions Flashcards Official chapter

Ch. 9 Inspecting air brake components (pp. 26–28)

Lining must touch the drum when applied and be clear when released; cracked, loose, missing, oil- or grease-soaked or too-thin lining is defective.
Chamber size is the diaphragm area in square inches; both ends of an axle, especially a steering axle, need the same size.
Check chambers for leaks with spring brakes released and service brakes applied; factory vent holes are normal.
Slack adjuster effective length (camshaft centre to clevis pin) must match on each side of a steering axle.
Air lines are defective when damage reaches the reinforcing or inner layer; improper fittings or repairs are prohibited.
Tanks must be securely mounted; inspect the compressor with the engine stopped; a loose, cut or frayed belt is defective.

Ch. 10 Inspecting system operation (pp. 29–37)

Low air warning: start above 90 psi with the ignition on, fan the brakes; it fails if it does not activate at or above 55 psi (major defect).
Build-up: lower pressure below 80 psi, close the trailer supply valve, run at 600–900 rpm; 85 to 100 psi must take two minutes or less (minor defect if longer).
Governor: cut-out must be 120–145 psi and cut-in at least 100 psi (minor defect otherwise).
Leak test, engine off, brakes fully applied for one minute: no more than 3 psi for a straight truck, tractor or bus, 4 psi for a tractor and trailer, 6 psi with two or more trailers (major defect if exceeded).
Tractor protection test: lines disconnected, open the trailer supply valve — it must close before 20 psi; then with the brake pedal held, no air may come from the service line.
Trailer spring brakes must apply when the trailer supply valve is pulled out.
Tug tests check that trailer and tractor spring brakes hold, the hand valve holds, and the service brakes stop the vehicle.
Drain the supply tank first; a lot of moisture from other tanks, or any oil, must be reported; a faulty drain valve is a minor defect.

Ch. 11 Inspecting brake adjustment (pp. 38–40)

Pushrod stroke must be inspected at least daily; the most common chamber size is 30.
Long-stroke chambers have square air ports, a trapezoidal stroke tag and markings; standard chambers have round ports.
Measure applied stroke with pressure above 90 psi, spring brakes released, gauges at 90–100 psi, engine off and the pedal fully applied.
Any stroke over the adjustment limit is a major defect.
In Manitoba only certified technicians and S-endorsed drivers may re-adjust manual slack adjusters; automatics needing regular adjustment are defective and go to a certified technician.

Ch. 12 Practical exam and S endorsement (pp. 41–48)

Bring wheel chocks, a watch with a second hand, the chamber sizes and types, a way to hold the pedal, and tools to mark and measure the pushrod.
To adjust a manual slack adjuster: press in the locking sleeve, turn the bolt until the lining meets the drum, then back off about a third of a turn and confirm the sleeve re-engages.
A type 30 standard chamber's adjustment limit is 2 in. (51 mm); type 30 long-stroke is 2 1/2 in. (64 mm).

Written in our own words from: MPI Professional Driver's Manual

FAQ

Manitoba Commercial study guide: common questions

What is the best way to use this Manitoba Commercial study guide?

Read one topic, then answer that topic's practice questions while the rules are fresh. Note the questions you miss, re-read those notes, and finish with a full practice test across all 18 topics.

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No. It is our own summary of the MPI Professional Driver's Manual. Use it to review, and use the official handbook when you need the exact wording of a rule.

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