Mules are slightly smaller than their horse parent, and when they grow they share traits of both a donkey (the long ears), and the horse (color, tail, etc.). A Mule in the grass.
For example, a 2014 Ford F-150 is considered a half ton truck but most variants can carry a lot more than 1,000 pounds in the bed. Since these terms are probably not going away any time soon, it's best just to think of them as smaller, mediumest, and more than medium.. (Pause for laughter).
Typical commercial US dump trucks are double-axle dually setups carrying about 10 cubic yards of material, which is about 10 short tons for typical materials like gravel or soil. A big, heavy-duty triple-axle model might reach 15 tons. A single-axle model based on a passenger truck might only hold 3 tons. A side-dump semi trailer might hold 30 tons.