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Cargo inspection, weight and balance

General Knowledge4 minManual section 3, 3.1, 3.2

Cargo loaded wrong or not secured is a danger to you and others. Loose cargo that falls off can cause traffic problems and kill people. Loose cargo can hurt or kill you in a quick stop or crash. An overload can damage your vehicle, and the way a vehicle is loaded can make steering harder.

What you are responsible for

Even if someone else loaded and secured it, you are responsible for:

  • Inspecting your cargo.
  • Recognizing overloads and poorly balanced weight.
  • Knowing your cargo is properly secured and does not block your view ahead or to the sides.
  • Knowing your cargo does not block your access to emergency equipment.

If you plan to carry hazmat that needs placards, you also need the hazmat endorsement and must pass the hazmat test.

Federal, state and local rules on weight, securing, covering loads and where large vehicles may drive differ from place to place. Know the rules where you drive.

Inspecting cargo

As part of your vehicle inspection, confirm the truck is not overloaded and the load is balanced and properly secured.

  • After starting: check the load and its tie-downs again within the first 50 miles. Adjust as needed.
  • Re-check as often as needed to keep the load secure. Inspect again after driving 3 hours or 150 miles, and after every break you take.

Weight definitions

You are responsible for not being overloaded. Know these terms:

  • GVWR (Gross Vehicle Weight Rating): the value the manufacturer sets as the loaded weight of a single vehicle.
  • GCWR (Gross Combination Weight Rating): the value set by the manufacturer of the power unit (if shown on the FMVSS label), or the sum of the GVWRs or actual weights of the power unit and towed unit(s) that gives the highest value. (Roadside officers use this to decide if CDL rules apply.) GCWR is a rating; the gross combination weight (GCW) is what the loaded combination actually weighs.
  • Axle weight: the weight one axle or one set of axles puts on the ground.
  • Tire load: the most weight a tire can safely carry at a given pressure. It is written on the side of each tire.
  • Suspension systems have a manufacturer's weight capacity rating.
  • Coupling device capacity: coupling devices are rated for the most weight they can pull and/or carry.

Legal weight limits and the bridge formula

Keep weights within legal limits. States set maximums for GVWR, GCWR and axle weights.

Maximum axle weights are often set by a bridge formula. It allows less weight on axles that are closer together, to keep bridges and roads from being overloaded.

Overloading hurts steering, braking and speed control. Overloaded trucks must go very slowly up hills, and worse, they may gain too much speed going down. Stopping distance increases, and brakes can fail when forced to work too hard.

In bad weather or in the mountains, it may not be safe to drive at legal maximum weights. Think about this before you go.

Do not be top-heavy; balance the weight

The height of the center of gravity is very important. A high center of gravity (cargo piled high, or heavy cargo on top) makes you more likely to tip over, especially in curves or when you swerve. Load cargo as low as possible: put the heaviest parts under the lightest.

Poor balance makes handling unsafe:

  • Too much weight on the steering axle: hard steering; it can damage the steering axle and tires.
  • Under-loaded front axle (weight shifted too far back): the steering axle is too light to steer safely.
  • Too little weight on the drive axles: poor traction; drive wheels spin easily, and in bad weather the truck may not be able to keep going.
  • High center of gravity: greater chance of rollover. On flatbeds, the load is also more likely to shift sideways or fall off.

References and scope

The topic reference is listed below. Sources support verification; the lesson itself is here. The current content needs technical and language review before public launch.

Manual reference: 3, 3.1, 3.2

Official CDL handbook · Utah ↗StatesOur editorial approach

Put it into practice

Educational questions with explanations. The answer review also works without the interactive quiz.

Preparing your questions…

Review questions with answers

  1. If someone else loads and secures your cargo, who is responsible for inspecting it and knowing it is secure?
    1. The shipper only
    2. The loader only
    3. The receiver
    4. You, the driver
    Show answer
    You, the driver

    Whether or not you load it yourself, you are responsible for inspecting the cargo and knowing it is properly secured.

  2. Which is one of the four cargo responsibilities of a driver?
    1. Choosing the shipping rate
    2. Knowing the cargo does not block access to emergency equipment
    3. Signing customs papers
    4. Pricing the load
    Show answer
    Knowing the cargo does not block access to emergency equipment

    Drivers must inspect cargo, recognize overloads and poor balance, know it is secured and does not block views, and that it does not restrict access to emergency equipment.

  3. After starting a trip, you should inspect the cargo and securing devices again within the first:
    1. 50 miles
    2. 100 miles
    3. 150 miles
    4. 25 miles
    Show answer
    50 miles

    Re-inspect within the first 50 miles and make any needed adjustments.

  4. How often must you re-check your cargo during a trip?
    1. Every 500 miles
    2. Once a day
    3. After 3 hours or 150 miles, and after every break
    4. Only at the end of the trip
    Show answer
    After 3 hours or 150 miles, and after every break

    Re-check after driving 3 hours or 150 miles, and after every break.

  5. Gross Vehicle Weight Rating (GVWR) is:
    1. The actual weight on a scale
    2. The value the manufacturer specifies as the loaded weight of a single vehicle
    3. The weight on one axle
    4. The weight a tire can carry
    Show answer
    The value the manufacturer specifies as the loaded weight of a single vehicle

    GVWR is the manufacturer's rated loaded weight of a single vehicle.

  6. "Axle weight" means:
    1. The weight of the axle itself
    2. The total weight of the truck
    3. The rated capacity of a coupling
    4. The weight that one axle, or one set of axles, puts on the ground
    Show answer
    The weight that one axle, or one set of axles, puts on the ground

    Axle weight is the weight one axle or set of axles puts on the ground.

  7. Where can you find a tire's maximum safe load rating?
    1. On the side of the tire
    2. On the registration
    3. On the fifth wheel
    4. On the bill of lading
    Show answer
    On the side of the tire

    Tire load is the most weight a tire can carry at a specified pressure, stated on the side of each tire.

  8. Coupling devices are rated for:
    1. Their age
    2. Their color
    3. The maximum weight they can pull and/or carry
    4. How fast they can lock
    Show answer
    The maximum weight they can pull and/or carry

    Coupling device capacity is the maximum weight a coupling can pull and/or carry.

  9. A bridge formula allows:
    1. More weight on axles that are close together
    2. Less weight on axles that are closer together
    3. Unlimited weight on bridges at night
    4. More weight in winter
    Show answer
    Less weight on axles that are closer together

    The bridge formula permits less maximum axle weight for axles closer together, to protect bridges and roads.

  10. Which is an effect of overloading a truck?
    1. Shorter stopping distance
    2. Better traction on hills
    3. Faster climbing on upgrades
    4. Brakes can fail from working too hard, and the truck may gain too much speed on downgrades
    Show answer
    Brakes can fail from working too hard, and the truck may gain too much speed on downgrades

    Overloading hurts steering, braking and speed control; stopping distance increases and brakes can fail.

  11. In which situation might it be unsafe to drive at the legal maximum weight?
    1. Bad weather or mountain driving
    2. Driving on a flat interstate in daylight
    3. Driving empty
    4. Driving at night on dry roads
    Show answer
    Bad weather or mountain driving

    Bad weather or mountain grades can make legal maximum weights unsafe. Think about this before you drive.

  12. To keep the center of gravity low, you should:
    1. Put the heaviest cargo on top
    2. Stack cargo as high as possible
    3. Put the heaviest parts of the cargo under the lightest parts
    4. Load all weight at the rear doors
    Show answer
    Put the heaviest parts of the cargo under the lightest parts

    Distribute cargo as low as possible, with the heaviest parts under the lightest parts.

  13. A high center of gravity is most dangerous:
    1. When parked
    2. In curves or when swerving to avoid a hazard
    3. On straight, flat roads
    4. When backing slowly
    Show answer
    In curves or when swerving to avoid a hazard

    A high center of gravity makes tipping over more likely, especially in curves or when you must swerve.

  14. What can happen if there is not enough weight on the front (steering) axle?
    1. The steering axle may be too light to steer safely
    2. Steering becomes very hard
    3. The tires will overheat
    4. Fuel use drops sharply
    Show answer
    The steering axle may be too light to steer safely

    An under-loaded front axle, from weight shifted too far back, can make the steering axle too light to steer safely.

  15. Too much weight on the steering axle can cause:
    1. Poor traction on the drive wheels
    2. Light steering
    3. A trailer jackknife
    4. Hard steering and damage to the steering axle and tires
    Show answer
    Hard steering and damage to the steering axle and tires

    Too much weight on the steering axle causes hard steering and can damage the axle and tires.

  16. Too little weight on the drive axles can cause:
    1. Hard steering
    2. Brake fade
    3. Poor traction, so the drive wheels spin easily
    4. A front-wheel skid only
    Show answer
    Poor traction, so the drive wheels spin easily

    Too little weight on the driving axles causes poor traction; in bad weather the truck may not keep going.

  17. Rules about vehicle weight, securing cargo, covering loads and where large vehicles may drive are the same in every state and city.
    1. True
    2. False
    Show answer
    False

    False. Federal, state and local rules vary from place to place. Know the rules where you drive.

  18. Gross Combination Weight Rating (GCWR) is used by roadside enforcement mainly to:
    1. Decide whether the driver and vehicle are subject to CDL rules
    2. Set the fuel tax
    3. Decide the toll price
    4. Choose the route
    Show answer
    Decide whether the driver and vehicle are subject to CDL rules

    The GCWR definition is used by roadside enforcement to determine whether a driver/vehicle is subject to CDL regulations.

  19. How is Gross Combination Weight Rating (GCWR) different from gross combination weight (GCW)?
    1. They are two names for the same number
    2. GCWR is the weight of the trailer only
    3. GCWR is a rating; GCW is what the loaded combination actually weighs
    4. GCW is set by the manufacturer; GCWR is measured on a scale
    Show answer
    GCWR is a rating; GCW is what the loaded combination actually weighs

    GCWR is a rating set by the manufacturer (or the highest sum of ratings/weights). GCW is the real weight of the loaded combination.