In Quebec and the rest of North America, all vehicles are divided into eight vehicle classes. This division is for regulatory purposes and is typically based on each vehicle’s weight capacity (not to be confused with driver’s license classes, such as Class 1 or 3 in Quebec). Each truck model has its own legal identity, and understanding these characteristics allows truckers to make informed choices and facilitates the repair of heavy trucks.

At Ressorts Industriels Laval / C.T. CAM, we know that this jargon is complex. We have created this simple guide to help our customers navigate best maintenance practices and to help our mechanics do their jobs.

How does the classification of heavy trucks work?

GVWR, or Gross Vehicle Weight Rating, refers to the maximum safe weight of a vehicle when loaded to full capacity. This number, calculated to ensure road safety, takes into account:

• Curb weight: the weight of the vehicle with its standard equipment and a full tank of fuel, without passengers or cargo.
• Passenger weight: the total weight of passengers in the vehicle.
• The weight of the load: the weight of everything that can be transported in the vehicle.
• Equipment weight: the weight of additions, such as the tongue and trailer.

This classification helps to enforce existing regulations, particularly for registration purposes and to assign models to the correct commercial designations. The GVWR is usually found on a plate on the driver’s side door.

The GVWR of heavy trucks

All vehicles, from humble golf carts to 18-wheel trucks, have a GVWR. Heavy trucks are classified as Class 7, 8, and 9. The heavy trucks we repair are typically semi-trucks carrying cargo, which are classified as Class 7 and 8.

Class 7 heavy trucks

Class 7 heavy-duty trucks have a GVWR between 26,001 and 33,000 lb (11,794 kg to 14,969 kg) and typically have 3 or more axles. Class 7 vehicles may include:

• Household waste dump trucks.
• Urban public transportation buses.
• Street sweeper trucks.
• Small semi-trucks.
• Trucks without trailers (such as moving trucks).

The Ford F-750 is a good example of a Class 7 heavy-duty truck.

Class 8 heavy trucks

Class 8 heavy trucks have a GVWR greater than 33,001 lb (14,969 kg). There is no defined upper limit for Class 8 trucks. Class 8 vehicles may include:

• Dump trucks.
• Cement trucks.
• Semi-trucks.

This is the type of truck we repair most frequently at the garage. Heavy-duty semi-trucks, which dominate the transportation industry, are the most common type in this class.

Other classifications of heavy trucks

Although there is no weight limit for Class 8 vehicles, there is another class of heavy vehicles. Class 9 vehicles include special-purpose trucks weighing more than 60,000 lb (27,215 kg). This class is necessary for transporting special and oversized loads on highways. For example, a semi-truck with an oversized load can weigh up to 80,000 lb and would be classified as Class 9. A heavy truck that meets these specific conditions must obtain special permits and use specifically designated routes, as many highways and bridges cannot withstand such high loads.

The different engine types

In the heavy truck sector, even diesel engines are classified into different categories. Diesel engines used in these vehicles are classified into the following service classes based on gross vehicle weight rating (GVWR):

• Light-duty diesel engines: used in vehicles belonging to classes 2B to 5.
• Medium-duty diesel engines: used in vehicles belonging to classes 6 to 7.
• Heavy-duty diesel engines or HHDDE: used in heavy-duty vehicles in Class 8 and above.

SAAQ regulations on heavy-duty semi-trailer trucks

The Preventative Maintenance Program (PMP) Inspection

All heavy vehicles are subject to the SAAQ’s Preventive Maintenance Program (PMP). Owners of these vehicles (whether businesses or individuals) must take them to an approved center or garage for a complete mechanical inspection, generally every 6 or 12 months depending on the age and frequency of use of the vehicle.

All heavy vehicles are subject to the SAAQ’s Preventive Maintenance Program (PEP). Owners of these vehicles (whether businesses or individuals) must take them to an approved center or garage for a complete mechanical inspection, generally every 6 or 12 months depending on the age and frequency of use of the vehicle.

Driver’s licenses

In the transportation industry, there are three classes of driver’s licenses:

• Class 3: Class 3 driver’s licenses allow the holder to drive a truck with two axles and a weight of 9,920 lb (4,500 kg) or more, as well as any other truck with three or more axles.
• Class 2: Class 2 driver’s licenses allow the holder to drive all trucks covered by a Class 3 license, as well as buses equipped to carry more than 24 passengers.
• Class 1: Class 1 driver’s licenses allow the holder to drive Class 2 and 3 vehicles, two-axle road tractors weighing more than 9,920 lb (4,500 kg) or pulling one or more trailers or semi-trailers.

Driving Hours and the Electronic Logging Devices (ELDs)

The operation of heavy vehicles for commercial purposes is subject to strict rules. In particular, there are several standards in place to regulate driving and rest hours. To ensure that transport companies and owners comply with the regulations, heavy trucks are equipped with an electronic logging device (ELD). The ELD records the movements of trucks that are subject to these regulations. It is sometimes referred to as the electronic “logbook” in the industry.

A garage for your heavy truck maintenance

If you need assistance with the maintenance of your heavy-duty trucks, please do not hesitate to contact us immediately. Our garage located in Laval can perform a variety of repair services to fix worn parts and ensure that your vehicle is in good condition for your work.