A heavy truck will be a party to regular servicing as is required by all commercial vehicles.
Truckers are a dedicated bunch, committed to hauling loads back and forth across the USA to keep the country running. Did you know that most domestic freight in the US is transported by road than any other form of transport? This is why we see so many heavy trucks on our roads – often in convoy – and also why we have a strong affection for these massive machines that are simply awesome to behold.
There are few countries where heavy trucks the likes of those familiar in the USA are regularly seen. Smaller countries such as the UK, for instance, have little need for such large trucks as there are fewer miles to cover, while Australia has its famous ‘Road Trains ’that eclipse even the US trucks in weight and cover great distances across the continent.
The following article looks at the maintenance of heavy trucks, and what needs to be done to keep them on the road. First, let’s have a look at what constitutes a heavy truck in US terms.
Trucks come in a vast array of shapes, sizes, and types. From the smaller vans we see in and around town to the big boys of the road that we are talking about here, they are all classed as commercial vehicles along with buses, coaches, taxis, and some agricultural machines that need to be moved by road. A truck is a vehicle used for carrying a load from one place to another, to give a broad definition. But want is a heavy truck, and why the distinction?
There are eight classifications of a truck, and these are determined by the overall maximum weight of the vehicle including the driver and load. Class 1, for example, includes the likes of popular trucks such as the Ford F150, which often doubles as a family car as well as a load carrier. The classes we are looking at are 7 and 8 – these are those trucks classified as Heavy Trucks.
How heavy can they be? To be in class 8 a truck must weigh 33,000lbs – and that’s the minimum! These trucks can carry loads of up to 80,000lbs on occasion, which gives an idea of the sheer power needed to drag such a vehicle across the USA. The most popular brand of the heavy truck is Freightliner, which commands more than 35% of the market share. Others include Mack, Peterbilt, Volvo, International, and many more huge, reliable and trustworthy trucks designed to last a long time.
However, like all vehicles, a heavy truck will need maintenance. Indeed, given the sheer mileage these vehicles cover and the conditions they encounter they are among the best-kept vehicles on US roads. There are laws and regulations covering truck maintenance designed for safety and compliance, but we are more interested in the maintenance routines as heavy truck needs to go through to stay on the road. This is not a job for the amateur as these are specialist vehicles, but there are some things a driver can do to help, so let’s start by looking at these. Before we move on, you might want to have a look at this inventory of heavy truck parts from Meritor which gives a good idea of what may be needed when servicing a heavy truck of this type.
A heavy truck will be a party to regular servicing as is required by all commercial vehicles, but in addition to this, there are a number of small checks that a driver will make when they feel the need. It is surprising how in tune with their vehicle truck drivers get, and they will notice any odd noise from the brakes, for example, or strange sensation in the steering immediately. Should this occur, they will contact the maintenance center as soon as is possible.
Brakes are a very important and sometimes complex area of the truck. Heavy truck brakes are air-powered rather than by hydraulic fluid as in your car. This is the best way of ensuring a safe stopping distance for a heavy vehicle. Before each journey, it is the duty of the driver to check that all the air hoses are connected securely. A heavy truck is a ‘semi-truck – ’in other words, it has a tractor cab that can be disconnected from the trailer – and when a trailer is hooked up the various airlines are connected as they need to be.
The driver will check this every time as it is not only for his or her safety but for that of other road users and pedestrians. The brakes will be overhauled regularly at services and new shoes or disks fitted. Often, the entire hub assembly – that which attaches the wheel to the axle and steering – is replaced as these are not repairable, and the whole assembly simply comes off to be replaced by a new one.
When you consider the mileage a heavy truck covers and the weight it is carrying it is also easy to see that the tyres and suspension will come under great stress and strain. This is why tyres, wheels, and the suspension system are checked regularly in order to ensure the truck is roadworthy and able to complete the long journeys required from it.
One further factor to remember is that a cab may be picking up a trailer that is waiting. This trailer will need checking separately from the cab as it is a different vehicle until the point it is hooked up to the tractor unit.
Basic checks such as these are performed alongside the regular eye kept on oil and water, which are essential to keeping the big and powerful engines running smoothly. An experienced driver, as mentioned above, will know instinctively when something is wrong and will be able to communicate the problem to the engineers responsible for repairing and maintaining the fleet or vehicle. What else is there to know about truck maintenance?
A regular service for a heavy truck will include the replacement of perishable items at sensible intervals. Items that have a limited lifetime will be replaced after a set number of miles, even if they appear to be operating properly. This sort of preventative measure enables trucks to keep on the road for many years and to cover hundreds of thousands of miles.
In recent years emissions laws have become much stricter so all trucks will need to undergo regular exhaust emissions checks to ensure they comply with the law. These laws will be tightened as the USA moves towards lowering the levels of dangerous gases emitted into the atmosphere, hence the need for trucking fleet managers to keep on top of the regulations at all times.
Given the vast number of vehicles on the road, we reckon that hundreds of heavy trucks will be undergoing routine maintenance as we write, while many more are traversing the highways of the USA fully laden with goods for the shelves in stores across the country.
The maintenance of these vehicles is carried out by an army of engineers and mechanics equally as dedicated as the drivers, and they should be applauded for the work they do in keeping heavy trucks safe, secure, and on the roads.
RELATED: Truck Brands (Pickup Trucks, Heavy and Medium-duty Trucks)
| Rank | Company | Country |
|---|---|---|
| #1 |  Volkswagen |
Germany |
| #2 |  Toyota |
Japan |
| #3 |  Stellantis |
Netherlands |
| #4 |  Mercedes-Benz Group |
Germany |
| #5 |  Ford Motor |
United States |
| Rank | Company | Country |
|---|---|---|
| #1 |  Michelin |
France |
| #2 |  Bridgestone |
Japan |
| #3 |  Continental |
Germany |
| #4 |  Goodyear |
United States |
| #5 |  Sumitomo |
Japan |
