If you’ve gone in for a new set of tires on your vehicle, then you’ve likely been annoyed by how expensive they can be, especially when you get all four at once. And yet, that’s nothing compared to putting a single new tire onto something like the Hitachi EH4000AC-3, a massive rigid dump truck with wheels that are each taller than a person—new tires on this beast cost tens of thousands of dollars. Fortunately, that’s not the kind of price tag most of us ever have to worry about, but it’s still remarkable to see such machines and the absolutely massive tires and wheels that go onto them. Let’s take a look at some of the biggest wheeled vehicles ever built (no tracks here, sorry Bagger 293) and the kinds of wheels and tires on them.
The Hitachi EH4000AC-3 Rigid Dump Truck
Undeniably, one of the largest and most impressive wheeled vehicles you might ever see is the Hitachi EH4000AC-3 rigid dump truck, which so far surpasses what its name might indicate, and words can hardly do it justice. When you see a “dump truck,” you probably think of something a construction crew uses to move dirt and debris—this thing is on another level. There’s a series of ladders and stairs necessary to reach the cabin where a driver sits, and its absolutely massive wheels are taller than a person. This monster can move more than 243 tons of payload, and it’s powered by an insane diesel engine.
You might’ve recently seen the next evolution of this series: the EH4000AC-5 that Hitachi unveiled last September. Footage of that behemoth has been making the rounds, and the new rigid dump truck they showcased can handle more than 266 tons, enhancing what’s previously been possible. This is an earth mover designed for industrial mining and similar industries, primarily in South and Central America. The beast of a machine weighs more than 360,000 lbs, and each tire costs about $60,000; I’m sure glad the tires on my truck only cost about half that.
The Cat 994F Large Wheel Loader
In case you’re wondering what kind of machine could possibly be used to get dirt and materials into something like the rigid dump truck we just looked at, here’s your answer. The Cat 994F large wheel loader is a similarly massive piece of machinery that’s used to scoop up bucketfuls of dirt just like any other wheel loader and dump them into something like the EH4000AC-3 (or another location at a site). At a glance, you could easily mistake this for similar, smaller loaders and just think it’s another piece of machinery you might find at a local construction site.
A better look, or one with an object for scale, will reveal that this machine is on another level completely. The Cat 994F can lift 35 tons of material in its monster of a bucket—the wide bucket option measures 244 inches! This incredible machine is one of the vehicles out there that can utilize the massive Firestone 70/70-57 tires, which are more than 157 inches in diameter and 74 inches wide. These incredible tires can sell for about $100k each, yes each, and they’re proudly made at a Firestone factory here in the US.
The F60 Overburden Conveyor Bridge
One of the coolest creations out there when it comes to a wheeled “vehicle,” the F60 Overburden Conveyor Bridge is a truly astounding piece of machinery. I’ll admit it’s kind of a stretch to call it a vehicle, but it can move, so I think it technically counts. Five of these goliaths were built by Volkseigener Betrieb TAKRAF in Germany; they went into operation in 1969 and remained in use until 1991. They were used in mining in Germany for transporting overburden, which refers to materials located on top of a coal seam. As you might imagine, that material needs to be cleared out to gain access to the coal beneath it.
These machines stand about 260 feet high and 790 feet wide, but I haven’t even gotten to the amazing part: they’re 1,647 feet in length. It’s essentially the size of a skyscraper lying on its side, and they’ve been referred to as a “lying Eiffel Tower,” in no small part due to how it looks as much as its size. The idea is that overburden could be removed from a location, transported along the conveyor, and deposited away from the coal. They have numerous sets of wheels so they can move—not very fast—ensuring they can be positioned as needed at their respective sites. You won’t see one of these cruising down the highway, but they’re certainly a testament to what can be accomplished by determined engineers.
The LeTourneau TC-497 Overland Train Mk II
LeTourneau, Inc., an American manufacturer of heavy equipment, started working on “overland trains” in the 1950s, developing them for potential use by the US Army. At the front is a large truck pulling a series of multi-wheeled vehicles behind it, each wheel driven by a motor to not overwork the vehicle at the front. They developed a number of different versions of this but the pinnacle was the TC-497 Overland Train, MK II that they were contracted by the Army to make in 1958. This beauty features four 1,170 hp engines: one up front in the control vehicle and the other three at other points on the train to help maintain power while moving.
With a 20-foot controller car, two power cars, and ten cargo cars all connected to each other, the full overland train was more than 570 ft long and could travel 20 mph even with 150 tons of cargo loaded onto those cars. This whole setup was surprisingly maneuverable and intended as a way to move cargo across any kind of landscape. It ended up in Yuma, Arizona, and though it did well in testing by the Army, it was ultimately abandoned in favor of helicopters for cargo transport; most of it was sold for scrap, though the control cab remains at a museum in Yuma.
The Bigfoot 5 Monster Truck
How could I write a list of the biggest wheeled vehicles and not include at least one monster truck? That would make me a monster! While there are plenty of impressive options to choose from like Grave Digger or Bone Shaker, I chose to go with the greatest of legends: Bigfoot. For no particular reason, I decided on Bigfoot 5, the fifth iteration of this remarkable machine, which utilizes two standard truck frames for the chassis and five-ton military axles. The stars of the show, however, are the incredible Firestone 120-inch tires that this monster rides on. Bigfoot 5 was built in the 1980s specifically to be able to handle these gargantuan tires, the same tires that had been used on several of the previous Bigfoot generations.
The Helepolis Movable Siege Tower
Finally, I’d like to remind you that massive vehicles with big wheels aren’t a purely modern innovation: they’ve been around for well over 2,000 years. The Helepolis, which is Greek for “taker of cities,” is a movable siege tower designed to let an attacking force roll up to a city’s walls and unleash absolute terror upon it. The most famous example of this was built for the Siege of Rhodes in 305 BC. These siege engines stood about 130 feet tall and 65 feet wide, riding on eight wheels that were each about 15 feet in height. They would be pushed into place by more than 3,000 men working together and had more than a dozen catapults plus numerous dart throwers (think ancient missile launchers) to lay siege to a city over its walls.
I Guess Those 22-inch Wheels Aren’t So Impressive
I’m as impressed by the next guy by things like 22-inch wheels or 33-inch tires on trucks these days, but it’s all about perspective. When you put those next to something like the massive wheels and tires found on industrial earth movers and dump trucks, they can look truly minuscule by comparison. It’s a matter of scale, and the massive tires on these vehicles are often the limiting factor in just how large a piece of machinery can get. After all, you can take a machine to a job site piece-by-piece and assemble it on-location, but tires must arrive fully completed. So a vehicle can only be as large as it can be in relation to the wheels and tires that support it—this is part of why the biggest vehicles often have tracks instead. Still, when you take a look at something like the Hitachi EH5000AC-3 rigid dump truck, the scope of what’s possible never fails to impress.
