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The avarage weight of a semi truck is 33 000 lbs.
Every major country engaged in commerce has weight restrictions when it comes to semi-trucks. Part of this is for safety. The heavier the truck, the greater damage it can cause. It’s hard enough for a truck driver to handle a normal-sized load. When we see trucks out there with double and triple loads, we just wait for an accident to happen.
The other thing about heavy truck is that they cause a lot of unnecessary wear and tear on major highways. That’s why there are weight limits for trucks that drive on any federally funded highway or road in the United States. The same is true in Canada and Australia. They want to protect their roads as much as possible so they don’t have to spend billions of dollars fixing them every year.
Years ago, the U.S. government put a federal weight limit on all commercial semi-trucks and tractor trailers. Regardless of what road the truck is on, it could not weigh more than 73,200 pounds. This changed to 80,000 in 1982 when they increased the weight limits. In 2011, they considered increasing this once again by another 11,000 but the legislation was denied.
Currently, truck drivers are arguing that the weight limit should be increased once again. They argue that this would benefit them in the following ways:
- it would increase driver and highway safety
- It would make it more efficient and more effective
However, common sense dictates that this is not a good idea. There is an argument to be made that heavier trucks are actually less safe than lighter trucks. And, there are other arguments against increasing the weight limits as well:
- Companies would have to invest in entirely new fleets of trucks
- It would cost more to fuel these vehicles
- Shippers aren’t going to pay more for bigger loads so would actually be less cost-efficient
For now, it doesn’t look like the law is going to change, at least not in the U.S.
What are some of the Common Weights for Semi-Trucks in the U.S.?
Truck manufacturers are well aware of the weight limits for tractor-trailers in the U.S. Depending on the Class of the vehicle, there are different weight allowances. Some of the most common weights of popular semis in the U.S. are as follows.
The average weight of a semi-truck is 33 000 lbs.
Class | Category | Weight (lbs.) | Makes and Models |
6 | Medium Truck | 19,501-26,000 | Chevy Kodiak
Int’l Durastar Peterbilt 330 Ford F-650 |
7 | Heavy Truck | 26,000-33,000 | Ford F-750
Peterbilt 220 Peterbilt 337 GMC C7500 |
8 | Heavy Truck | 33,000 and up | Freightliner Cascadia
Kenworth T600 Kenworth T660 |
How is Weight Calculated for Semi-Trucks?
When it comes to determining and measuring the size and weight of semi-trucks, it isn’t all that complicated. There are three (3) main types of weights as far as the federal government is concerned. Each of these vary based on what is included in the weight of the semi-truck. For example, some combine the fuel while others simply look at the combined weight of the cab and trailer.
Gross Vehicle Weight (GVW):
This is the total weight of the loaded vehicle – the vehicle plus the cargo it’s carrying
Gross Combination Weight (GCW):
This is the maximum suggested load amount (according to the truck manufacturer) plus the weight of the trailer or semi-trailer
Gross Vehicle Weight Rating (GVWR):
This is the amount the truck weighs when it’s filled with both fuel and its full load.
What are the Normal Dimensions of a Semi-Truck?
It’s not just the weight of the truck that matters. The size also matters. The average length of a semi-trailer is about 70-80 feet. The average height is 13’6” and the average wheelbase is 245-246 inches.
All of these things help determine what kind of load a truck can carry. While the longer trucks can carry more flat loads, sometimes the taller trucks are used to carry stacked loads. It really depends on what kind of cargo a truck is designed to carry as to what sort of dimensions the truck’s fleet will be.
Auto manufacturers that make these semi-trailers understand the weight limits. In fact, it is the manufacturers who make the load and weight recommendations. For example, when it comes to the GCW, a trucking company is supposed to follow the guidelines set by the truck’s manufacturer. If they don’t, they can overload the truck and cause an accident.
What are the Major Differences Between a Semi-Truck Other Vehicles?
Tractor trailers are obviously a lot different from a regular car. Some of the ways in which a semi-truck stands out is broken down below. It’s interesting to keep these points in mind when you’re complaining about how scary and intimidating tractor trailers are. It’s no surprise that people are afraid to share the road with these monster machines. Once you see the capabilities of a semi-truck you’ll understand why.
- Semi-trucks have an engine that is 6 times bigger than a regular car
- The average horsepower for a semi-truck is about 400-600 where it’s only 200-400 for the average car. In fact, most cars are a lot closer to 200 than 400. Any car with horsepower over 250 is considered fast.
- Semi-trucks are destined to go for up to 1 million miles. When you think about it, a solid car is only expected to go 150-200K miles. So, a million miles is about 6-7 times as long as the life of a regular vehicle.
- Trucks have as many as 12 different gears. This is why they’re so much harder to operate than a standard vehicle. This is also why so many people have to go to truck driving school to learn how to operate one of these machines.
- Semi-trucks can run non-stop. They don’t need breaks and they don’t need to rest. You don’t have to worry about a semi-tractor trailer overheating or breaking down like you do with a regular car or SUV.
- All semi-trucks have an air-braking system. Cars do not have this. This is necessary when you think about how hard it is to stop such a large vehicle. They also need to make frequent stops so an air-braking system is a lot more efficient and a heck of a lot safer.
- Semi-trucks all have turbo charging systems. This makes it easier for them to get power to the combustion engine.
- Most semi-trucks run on diesel fuel rather than gasoline. There are a few pickup trucks that run on diesel, but not many.
How Much Do Semi-Trucks Cost?
When it comes to costs, semi-trucks are very expensive. In fact, they’re a lot more expensive than most people think. It costs about $30,000-$80,000 for the trailer. Then, it’s another $130,000-$180,000 for the truck’s cab. This gives it an overall price of anywhere from $160,000 to $260,000!
One of the reasons it can be hard for a trucker to afford their own cab and trailer. In fact, just affording the cab is difficult. When you think about it, the cab of a semi-truck costs more than most people’s first homes. When truckers are able to afford to finance their own truck, it can make their job more profitable. However, it can also take 10-20 years to pay that truck off. This is why it’s important that semi-trucks are so durable. If it’s going to cost this much for a cab and trailer, you want to make sure you get all the mileage you can out of it.
What if a Truck Weights More than the Legal Limits?
When the U.S. government passed the law in 1982 increasing the maximum weights to 80,000 pounds, they grandfathered in any vehicles that were already more than that. For instance, trucking companies that had vehicles with a combined weight higher than 80,000 were still allowed on the road. They were immune from the new laws regarding weight restrictions. However, once these trucks were off the road, that was it. All new cars manufactured after 1982 had to be less than 80,000 total pounds.
Ovearll, more than 90% of all semi-trucks do weight less than 73,000 pounds. Since 80,000 is the load limit, it’s better for trucking companies to maintain a fleet of trucks that cap out at 73,000. This allows them a bit of leeway when it comes to super-sized loads. Being able to add an additional 7,000 pounds of cargo can make a big difference in shipping.
Companies can also apply for oversized permits. If a truck is going to have a combined weight of more than 80,000 pounds, the trucking company can apply for a special permit. These are not given away willy nilly. You have to justify the additional weight. You also have to pay special permit fees. And when your truck enters the mandatory weigh-in stations, they need to show proof that they’re allowed to exceed the maximum weight of 80,000 pounds.