Vroom! Vroom! Do you like to play with cars and trucks in the dirt? We do! If you're like many kids, you probably enjoy building your own custom construction scenes, complete with lots of working trucks.

Our favorite truck, of course, is the dump truck. We love to fill its bed with rocks and dirt before pushing it across the rough terrain of the backyard. When it gets to the construction site, we make mechanical noises as we lift the bed, spilling its contents onto the ground.

In the real world, dump trucks are used to haul large loads of loose materials, such as dirt, rocks, sand, and coal, to construction sites, factories, or power plants. The open bed features a hinge at the rear of the truck, so that hydraulic pistons located at the front of the bed can lift the front to dump the contents of the bed at the delivery site.

Of course, dump trucks are big. They have to be! How much loose dirt or coal could you haul in the trunk of your family sedan? Or even in the back of a regular pickup truck? Not much…at least compared to the large loads dump trucks can carry. That's why dump trucks usually have large diesel engines and anywhere from six to a dozen tires.

To find the largest dump trucks in the world, you need to check out large open-pit mining operations. As companies mine the ground for coal and other valuable resources, huge dump trucks are needed to carry the extremely-large loads of dirt, coal, and rocks that are taken out of the ground. And the more a dump truck can carry, the less it costs the mining company per load to haul its resources.

For several years, the world's largest dump truck was the Caterpillar 797B. Standing 25 feet high and nearly 50 feet long, this $5 million behemoth couldn't be driven on the highway. Instead, it had to be transported in pieces and assembled at a job site.

The title of world's largest dump truck went to a new vehicle recently, however. Manufactured by BelAZ in Belarus, the BelAZ 75710 began moving rocks and coal in a mine in Siberia in 2014. So how big is the BelAZ 75710? It's as long as two buses parked end to end, six times more powerful than modern Formula 1 racing cars, and heavier than a loaded Airbus A380 airplane!

Hard to imagine, isn't it? To help put its size into perspective, a six-foot-tall adult standing next to the BelAZ 75710 wouldn't even reach halfway up one of its eight gigantic tires. Speaking of tires, each one of this massive dump truck's tires stands over 13 feet tall and weighs nearly six tons. Each tire also costs over $42,000, which helps to explain why the entire vehicle costs over $6 million!

Those huge tires help the BelAZ 75710 carry an enormous payload of around 500 tons. A dump truck needs more than just strong tires, however. The BelAZ 75710 hauls so much weight with the help of a unique engine system. Two 16-cylinder diesel engines power generators that supply electricity to four 1,200-kilowatt electric engines. The end result is an 1,800-horsepower dump truck with an unmatched hauling capacity.

If you're WONDERing why BelAZ chose to develop the world's largest dump truck with electric motors, the company wanted to maximize fuel efficiency while also meeting tougher environmental regulations that govern vehicle emissions related to mining operations. The BelAZ 75710 is able to operate more economically while also being more environmentally-friendly.

Wonder What's Next?

Tomorrow’s Wonder of the Day features some creatures that never, ever say, “School’s out!”