A 20-ton dump truck carries 67-80 cubic yards of mulch (500-600 lbs/yard), 18-20 cubic yards of topsoil (2,200 lbs/yard), or 12-13 cubic yards of sand (3,200 lbs/yard). Multiply material weight by volume to calculate loads.

Material Weight and Density

The capacity of a 20-ton dump truck depends mostly on the weight and the density of the material being transported, and for mulch, the general average weight is 500 to 600 pounds per cubic yard. With a 20-ton capacity, the amount equivalent to 67 to 80 cubic yards of mulch is what the truck can carry. At this rate, this amount will sufficiently serve 1,600 square feet to 1.5 inches deep, which is essentially the deep required for landscape or garden coverage.

Common topsoil used in gardening and building has an approximate dry density of about 2,200 pounds per cubic yard. Given that fact, a 20-ton dump truck would then carry about 18 to 20 cubic yards. That's 1,200 square feet at a depth of 6 inches for filling a garden bed or evening out an uneven ground area. Topsoil For wetter applications, the density can get as high as 2,600 pounds per cubic yard, which puts the capacity of the truck at only about 15 to 16 cubic yards, so that has to be considered when working on projects that are conducted during rainy parts of the year.

Gravel, also in wide usage for drives and drainage, is heavier, averaging 3,000 pounds per cubic yard. That means a 20-ton truck can carry 13 to 14 cubic yards of gravel. For a typical driveway, which is 10 feet wide, 50 feet long, and has a depth of 4 inches, one load of gravel should be enough.

Another common material carried by dump trucks is sand. Sand is approximately 3,200 pounds per cubic yard, which means that a 20-ton load could hold roughly 12 to 13 cubic yards of sand. That is sufficient to fill a sandbox measuring 10 feet by 10 feet and having a depth of 3 feet. Wet sand, with its higher moisture content, can weigh as much as 3,500 pounds per cubic yard, and the capacity of the truck reduces to about 11 cubic yards.