Dump vehicles come in a dizzying array of configurations - standard dump truck, Superdump, transfer dump truck, truck and pup, tractor with end dump trailer, tractor with side dump trailer, tractor with bottom dump trailer, etc. And each of these options can be further customized.
To find the best solution for your applications, you really need to understand the benefits and trade-offs associated with each choice, then match that with your operation and regional regulations.
Standard dump trucks
The short wheelbase of a standard dump truck makes it more maneuverable than tractor/dump trailer combinations. The downside to this configuration is often limited capacity when operated in Bridge Formula states. But there are regions of the country where conventional straight trucks can haul loads competitive with tractor/trailer combinations.
Taylor Services Inc., Blairsville, PA, is a dump truck operation using both four-axle dump trucks with tridem rear axles and tractor/end dump combinations. "We operate about 75 units," says Jeff Taylor. "We are probably two-thirds straight truck and one-third tractor and trailer." This is primarily due to the local regulations in Pennsylvania, and the fact that the company performs most of its work inside the state.
"We are able to haul 73,280 lbs. on a four-axle unit," says Taylor. The trucks are equipped with Trail King square boxes. "We dump as many as 23 loads a day, so we are testing the dump portion pretty strongly."
Maneuverability is important in the company's operations. "Because we are dealing with mine sites and construction sites where space is sometimes limited, the straight truck just gets you in tighter spots," Taylor states.
Taylor Services Inc. also runs 39-ft. end dump trailers, but claims the straight trucks are a safer alternative. "From a dumping standpoint, it is much more stable than a tractor/trailer. Basically, you are putting 20 ft. in the air, rather than 40 ft."
In Pennsylvania, the difference in allowable capacity between straight trucks and end dumps is negligible. "Our tractors and trailers with the 39-ft. frameless end dumps can net about 48,000 lbs.," Taylor asserts. "With our tri-axles, we are netting 47,000 lbs. So the legal payload capacity is about the same."
One of the advantages of tandem and tridem configurations is less complexity compared to pusher and tag axles. "Anytime you add more axles, more tires, more parts, not only does the initial cost go up, the cost to maintain and operate has to go up, as well," says Taylor.
For many states with bridge laws, a day cab tractor pulling a dump trailer will allow maximum payloads. One of the most common is the end dump. The key advantage to the end dump trailer is rapid unloading.
Taylor Services Inc. has quite a few Trail King end dump trailers, primarily for its interstate jobs. "We get into Maryland, West Virginia, Virginia and Ohio - our surrounding states," says Taylor. "The 39-ft. end dump trailer gets us long enough to comply with the Federal Bridge Formula."
Due to the stability issues with end dump trailers when unloading, you don't want just anybody behind the wheel. Taylor stresses it takes a little more training. "You need a little more conscientious individual, no question," he states.
But Taylor believes the benefits of the end dump outweigh the downsides. "The paving equipment - all of the equipment that we do road work with in this area - is set up for end dumps," he explains. "All of the power plants, all of the mines, the bins are set up for end dumps."
Side dump trailers are an attractive alternative for many regions of the country. "Because the tub dumps to the side, there are no restrictions on trailer frame length or axle location," says Rick Lawrence, national sales manager, SmithCo Mfg. "The maximum weight allowed in any state can be achieved, which means better payloads. You can pull doubles and not have to unhook."