The U.S. economy would flounder if it weren’t for the trucking industry. Semi-trucks are responsible for transporting about 71% of America’s freight, and there are about 8.9 million people in the trucking industry. While we’re all used to seeing semi-trucks barreling down the highway, many people don’t know how many miles-per-gallon semi-trucks get.

Semi-trucks and gas mileage

Transporting freight from one location to another isn’t cheap. We all pay so much for shipping because semi-trucks are gas guzzlers. In the early ’70s, it was estimated that the average semi got about 5.6 MPG, but that amount has increased slightly. In 2014, new semi-trucks were required to get 7.2 MPG on average.

Hills have the biggest impact on a semi-truck’s fuel economy. It’s not unusual for a semi’s gas mileage to drop to under 3 MPG when it’s going up a steep hill. Going down that same hill can bump the mileage up to 23 MPG.

Other factors that impact fuel economy include wind resistance, the weight of the load the truck is hauling, the condition of the tires. A strong desire to make shipping freight more affordable has prompted designers to look at ways they can use technology to alter semi-trucks, making them eco-friendlier.

Most of the semi-trucks you see are from one of three states

While each state has some registered semi-trucks, most of the ones you see are based out of three states. According to registration information, 1/3 of the currently licensed semi-trucks are owned by trucking companies located in Texas, California, or Florida. You may also be surprised to know that the size of the average trucking business is quite small.

Data indicates that about 90% of the trucking companies located throughout the U.S. only own about six trucks. One reason so many trucking companies have so few vehicles could be because many of the registered trucking companies are a driver/owner who only operates one vehicle which they use to freelance for other companies.

Semi-trucks pull a lot of weight

It’s no secret that semi-trucks haul big loads, but most of us don’t realize just how much weight they tow. While some specially designed vehicles carry larger loads, the average semi-truck can pull 80,000 pounds. All that weight is why truckers worry when vehicles cut them off on the highway. They’re pulling too much weight to stop on a dime.

Semi-truck drivers are highly trained

Not everyone has what it takes to drive a semi-truck. The first thing you need is a Class A driver’s license, which allows you to drive heavy vehicles that pull massive amounts of weight. Qualifying for this highly specialized license requires that you know rules pertaining to how many hours a driver can operate before they must take a break, how to properly file and store the paperwork that must be in the truck, weight restrictions, as well as some other laws the average motorist doesn’t know about.

You must pass a difficult driving test before you’re allowed to take a semi-truck out on the open road. In addition to needing a special license, you also need the right personality. If you want to be a long-haul driver, you must be willing to sleep in your vehicle and spent lots of time away from family. Your reward is a good paycheck and the ability to see parts of the country most people miss.

If you’re a short distance hauler, you get to spend most nights at home, but you most likely will drive the same route all the time, which can become tedious.