You may also run across speed ratings. This is an area for caution. Some tires are rated for higher loads at a reduced speed. Even though federal law permits placing a dual rating on the trailer, McClure notes that many states do not recognize these ratings. So this is something you might want to avoid. He adds, "In most of our applications, the tire rating exceeds the axle capacity."
"I think the dual rating is kind of misleading to the customer," comments Odegaard. Dynamic forces on the trailer are greater at higher speeds. "The capacity of the trailer does go up at slower speeds, but we will not rate it that way. We rate ours at highway speeds."
Ladner agrees, adding, "If the road is safe at 70 mph, then that driver is going to want to travel safely at 70 mph. When you start to throw restriction in, then typically you get customer abuse on the product."
Finally, you have to realize that trailer ratings are absolute. "Operators sometimes think, ‘I am only going to [exceed the rating] once a month,' " says Ladner. "It is just not safe when you exceed the ratings on the trailer, truck or piece of equipment."
By moving to a larger trailer that will handle the most demanding jobs, you will actually get longer life. "Even though you might invest a little more money up front, you will get the return back with the service out of that product," says Ladner.
Trailer weight is not as critical as load capacity. "For example, a lot of people will buy our 20-ton tag trailer, but will only be putting from 10 to 15 tons on it," says McClure. "They can probably put only 17 tons on it legally before they are exceeding legal requirements of the tandem on the trailer."
The same trend occurs with lowboy trailers. "People will buy our 50-ton trailer, but they will put anywhere from 70,000 to 100,000 lbs. on it," says McClure. "They will have multiple pieces of equipment, and they buy the slightly bigger trailer just to have a trailer that could handle anything."
Deck materials expand
Oak and Apitong are traditional deck materials. "Oak is still the most common, replenishable wood you can put on it," says McClure. "Apitong is a significant upgrade. It is pre-dried and it doesn't warp."
But there are advancements taking place in alternate materials. "We are trying to get into some different kinds of decking for trailers," says Odegaard. "One is called Rumber; it is a rubber compound decking. Hopefully, with tracked equipment, the decks will last a little bit longer."
Another option is a bamboo composite. "We are testing both of these alternatives to Apitong," says Ladner.
The goal is to increase the deck life to more closely match the trailer life. "When you are talking about equipment that will last 15 to 20 years, if you stay with Apitong, you might be talking about two to four deck replacements," says Ladner. "Rumber is in the same 15- to 20-year life cycle. So the decking might last the life of the trailer."
Low cg and load angle
Low load angles benefit all equipment. This has led to innovations such as the traveling (or sliding) axle trailer, which was introduced in 1970. "It has been well accepted in the construction industry as a transport for 80% of the equipment used," says Ladner. "You can load low-clearance equipment really well, and you can haul multiple pieces on a deck that is up to 53 ft. long."
"The big advantage to the sliding axle is load angle," says Odegaard. "You get a much better loading angle than you do with a beavertail or a tilt bed."
However, the center of gravity (cg) is always a concern when moving equipment. "It makes the load a lot more stable and it is safer for the equipment operator to load if you keep the cg down," says Odegaard.
While tag and sliding axle trailers are popular with many contractors, there are issues with equipment that has a high cg. "With a tag trailer, you are loading above the tires," says Odegaard. "So you are probably starting out at 3 ft. high."
This is where the detachable gooseneck trailer really shines, since it lowers equipment to the ground. But some contractors are also discovering the benefits of combining the low cg of a detachable gooseneck with low load angles.