One of the greatest arms races in the auto industry is within the full-size, heavy-duty truck market. It seems like every year we have a new king of towing capacity. When you see those world-beating, best-in-class stats, it’s not just any truck that’s putting up those numbers. The highest towing capabilities are almost always found in the dually variant of a given truck. When you need to tow and haul more than the average pickup can handle, a dually is the only way to go.
What Does ”Dually” Mean?
Dual-Rear Wheel, DRW, or “dually” trucks (often mispelled as "dully" trucks) are defined by the way their rear axle and wheels are configured. They feature four rear wheels, with two wheels sandwiched together on either side of the rear axle. Thanks to the doubled-up rear wheels and the flared fenders that accommodate them, duallies are unmistakable from any other kind of truck.
This style of truck is almost exclusively offered in the heavy-duty line of a pickup, and it’s often the more capable variant. Think of the Ford F-350 Super Duty, or the Chevrolet Silverado 3500HD. These are the largest, most powerful, and most capable versions offered by each respective brand. The same goes for the GMC Sierra 3500HD and the Ram 3500 Heavy Duty. Depending on the make and model, a dually truck can be optioned as a single cab, extended cab, or crew cab truck, and it’s often also available in standard-bed and long-bed configurations.
The sheer number of variations within the truck segment showcases all the different ways in which trucks are used. Single-cab trucks with long beds are pure work trucks. There are also spacious quad-cab truck models; these can do the work, but they can also handle a commute, a road trip, or picking up the kids from school or practice. There are dual-rear-wheel trucks that offer this mix of capabilities, too, but they are really designed for maximum towing and hauling. These big, wide trucks blend the line between consumer trucks and commercial vehicles.
What Are Dually Trucks Used For?
Engines today are more powerful than ever, with trucks like the Ram 3500 and Ford F-350 Super Duty both capable of more than 1,000 lb-ft of torque (for context, your typical family sedan puts out between 150 and 250 lb-ft). But all that power is only as good as the way in which it’s put to the road. Too much power, and the wheels can slip. That’s what makes the difference in getting a trailer up a hill or successfully lowering a boat down a ramp.
Just as importantly, duallies have an exclusive safety element to offer: The extra wheels let them remain stable in the event of a tire blowout. If you’re towing a 40-foot horse trailer on the highway, this redundancy is extremely important.
Some of the biggest trailers require duallies to tow them. Be it a large camper trailer, a heavy load of materials, or an enclosed trailer with multiple cars, it’s not just their extremely capable powertrains and chassis that allow dually trucks to hit the massive necessary towing numbers. The way the trailers hitch up is just as important. You can’t hit the advertised “best-in-class” trailering number simply by using the conventional hitch off the rear bumper. It often requires using a “fifth wheel” hitch or “gooseneck” hitch.
The fifth wheel is a dedicated receiver hitch that’s mounted in the bed of the truck. It’s called the fifth wheel because half of the large, flat C-shaped structure looks like a wheel. It’s similar to the hitch you’d see on the back of a semi-truck—which should give you some idea of how strong they are. The gooseneck hitch is similar to the fifth wheel. It’s mounted in the bed of the truck, and both are highly specialized. Many types of trailers are optimized for both of these types of hitches, and the trailers themselves have cutouts so that a large usable portion of the trailer is positioned directly over the rear bed area and the hitch.
With a dually, you can tow more than any other vehicle short of a commercial- or military-grade dump truck. When properly equipped, the Ram 3500 HD can tow a best-in-class 35,070 pounds. The Ford Super Duty can tow up to 37,000 pounds, but that requires selecting the F-450 Super Duty, so Ford isn’t exactly playing fair in its gooseneck and fifth-wheel claims. That said, Ford also has the most conventional towing (21,000 pounds), which is achieved in the F-350 DRW 4X2, Regular Cab, with an 8-foot bed and 7.3-liter gas V8 engine. The point is, hitting these claimed numbers often requires very specific configurations.
Are Dually Trucks Expensive?
Those very specific configurations aren’t cheap. Dually trucks are often the most expensive examples of a given truck, due in large part to all the other high-capacity running gear that comes with them. They often have the most powerful engines in the lineup, specific rear axle ratios, and other highly specialized gear for the greatest towing and payload capacities. If this is a purchase for personal use, that’s quite the big-ticket item, but rest assured that the added capability of dually trucks helps preserve their resale values. Of course, if you run a business, you can justify such an outlay by spreading the cost over the number of years you plan on using it for work.
Many dually trucks are used for job sites, and that often means going from point A to point B with minimal stops. But if you are interested in one of these trucks as a personal vehicle, just know that day-to-day driving will always be a challenge. Will there be enough open parking spots? Will it fit down that road? Will I have to pay more at the toll? These are all real questions that need to be addressed if you’re considering dually ownership.
On top of all those other considerations, there’s that of fuel economy. Because heavy-duty trucks are considered commercial vehicles, the automaker does not have to post EPA fuel-economy estimates (which is wild, considering how many heavy-duty trucks are now for personal use). Duallies are the heaviest and least-efficient consumer trucks on the road. Diesel engines are common in dually trucks, which will help the numbers on paper, but diesel fuel can be expensive, and so can the diesel engines themselves. Though Duallies often make up for their poor fuel economy with large fuel tanks or even dual fuel tanks, that still won’t account for the hit your bank account is going to take on weekly fuel bills.
Do I Need a Dually?
We said the venerable dually looks unlike any other kind of pickup truck. There’s one loose exception, and that is the flare-side pickup truck. Flare-sides also have pronounced fenders, but they’re only single-rear-wheel (SRW) setups. Flare-sides, style-sides, and step-sides all feature those flared fenders, and some have steps cut into the side before or after the fenders. This was a very function-over-form style of truck, and while the bed was more uniform for large boxes, they didn’t have the same space or capability that full-bed trucks offer. However, their short wheelbase, unique design, and the fact that truck-makers have stopped building them make non-dually flare-sides highly desirable as collectibles… just not as work trucks.
So dually trucks are expensive, inefficient, and cumbersome around town. So why spend all that money? Because dually trucks can simply do more. They have the highest tow ratings, and they can haul more than any other truck in their lineup. And though we often talk of the towing abilities, we’d be remiss if we didn’t mention how much these trucks can haul in their beds. Because the weight is spread over twice as many wheels, the dually setup can haul a lot while putting less stress on those hard-working rear wheels. This allows truck owners to put a load of material in the bed or haul some heavy machinery, all without the use of a trailer.
Despite their highly specialized intent, dually trucks are still daily driven and used as personal vehicles. Automakers recognize this and have started loading up modern heavy-duty trucks with all the same modern tech and safety features as the rest of the lineup. You can get massive touch screens, Apple CarPlay, Android Auto, heated and ventilated seats, panoramic moonroofs, and more. So much for work vehicles! But even modern dually trucks offer (typically optional) high-tech safety features like the ones found in most passenger cars today. There are even available camera systems and self-parking systems that solve for the headaches of backing up a large trailer. These features make big-truck hauling more realistic, even for novices.
And yet these trucks still have the tools needed for the worksite, such as the bed steps integrated before and after the rear fenders in the GMC Sierra HD and Chevy Silverado HD. The GM trucks as well as those from Ford and Ram also offer features like spray-in bed liners, in-bed lighting, and in-bed power outlets. Automakers, dealerships, and aftermarket outfitters offer plenty of customization options, including up-fitter packages for specific industries and professions.
These days, trucks are asked to do a heck of a lot. They are now comfortable commuter cars, family haulers, and road-trip rigs. They haul materials for weekend projects and toys like boats and campers. But at their core, pickup trucks are meant for work. And if you have to tow more than anybody else at the worksite, the “dually” is the truck for you.
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