Mack Trucks has built trucks for almost any conceivable application during its history. But every so often, something else comes along and raises the bar — sometimes literally.

Bronto Skylift, a Finnish company that for 50 years has manufactured some of the tallest aerial lift platforms in the world, has teamed with Mack and Nextran Truck Centers in North America to deliver its products to customers who need to work safely at extreme heights.

“Back in 2014, two gentlemen from Bronto came into the dealership with a drawing in hand and asked if we could do a truck to match it,” says Barry Sessions, a Nextran salesman. “We agreed that Granite would work best for what they were trying to do.”

It takes a special truck to provide a stable and reliable base for Bronto’s aerial platforms. Janne Pulkkinen, vice president for Bronto’s North American business, says a “small” Bronto reaches 230 feet into the air. The latest version built for this market reaches 295 feet high, and next year the company plans to deliver the first of its 341-foot (104-meter) platforms, the tallest in North America. (For comparison, the Statue of Liberty, including pedestal, is 305 feet tall.)

Mack is meeting this challenge with Mack® Granite® and TerraPro™ chassis equipped with as many as eight axles apiece.

Close coordination with Mack’s Sales Engineering department and Body Builder Support Team, along with Bronto North America’s local Mack dealer, Nextran Truck Centers of Orlando, produced Granite and TerraPro models with the specifications and engineering required to meet Bronto’s demanding applications.

Bronto has two main lines of business: firefighting/urban rescue and what it refers to as “access” or the ability to put workers into otherwise hard-to-reach positions. The access line has three main segments: wind power, utilities and general access. In the wind segment, customers use the platforms to reach windmill blades to inspect and repair them. Without the platforms, technicians would have to scale several hundred feet up the windmill, climb out to the exterior and descend on rope harnesses along the blade. That kind of extremely challenging physical labor, plus the required climbing skills, severely limits the number of qualified workers. And it has obvious dangers.

One of the characteristics of the Bronto platforms is their stability. They can typically be operated safely in winds up to 28 mph, but they can be designed for higher wind speeds, if necessary. Crews can be aloft in the platforms for their entire shift, which makes them more productive than other solutions which require more frequent descents. Large outriggers, similar to those seen on concrete pump trucks, provide a secure base.

Additionally, the trucks are configured so that the operator can raise the platform to working height and then shut down the truck’s engine from the platform. He restarts the engine and re-engages the PTO to drive the hydraulics when it’s time to move or lower the platform. This can save significant fuel over the course of a workday.

(Above) Diagram of an eight-axle Mack^® TerraPro^™ which will mount a 341 foot (104 meter) aerial lift platform from Bronto Skylifts.

The market for these trucks, while small, is growing strongly as the demand for wind power expands every year and as other industries discover the benefits of being able to provide a stable work platform for workers, as opposed to rappelling into position with rope harnesses.

As Bronto brought larger lift platforms to Mack, the design needed to change from the original four-axle design (including an auxiliary axle) to twin-steer and tri-drive. These five-axle Granites are capable of mounting a 230-foot aerial, such as the one delivered recently to Toronto Fire Services, the fourth-largest metropolitan fire department in North America. Tower One, as the unit is designated by TFS, is now the tallest fire truck in North America and fills a growing niche in emergency response operations.

“A significant issue in this city is vertical access,” says Rob Anselmi, TFS Division Chief of Mechanical Equipment and Asset Management, noting how much the city has grown in recent years with high-rise construction and in-fill housing. He also says the unit is outstanding for multiple other situations.

“It has some great specific uses, not just for high-rise applications. It has an incredible side reach that we’ve never had before, with incredible up-and-over capability. It could be on a house fire and be a block away and reach out and over. It’s for bluff rescues; it’s for crane rescues — there are so many construction cranes in this city right now.”

Even the most capable fire truck is useless if it can’t get to where it needs to go. Anselmi says that’s not much of a problem with the Tower One Granite.

“You would think, why buy this gigantic truck to drive around in a city that’s not easy to drive around in?” he says. That’s part of the reason TFS wanted the most compact unit they could get, with a maximum weight of 88,000 lbs. and a near 13-foot height. Tower One ended up 13 feet one inch tall.

“It’s actually the same length as our tandem axle aerial trucks, and it has less overhang from the rear axle due to the tri-axle,” Anselmi says. “This thing works so perfectly. Most of our drivers will tell you it actually drives easier than our custom chassis aerials.”

It’s hard not to appreciate Tower One, Anselmi says, and he knows other major cities are also interested in similar units. “It’s a stunning cab and chassis,” he says. “It really is an impressive truck.”

Bronto’s engineering requirements are not exotic by the standards of Mack’s Sales Engineering Department, according to Bill Borath, commercial project engineer. Mack builds several hundred twin-steer Granites on the Lehigh Valley Operations production line every year, as well as tri-drive trucks.

This experience is helpful when it comes to finding ways to place necessary components such as air and fuel tanks on a chassis containing additional wheels, outriggers and hydraulics. Sessions says he has a wealth of options to draw upon when working with Sales Engineering during the configuring and ordering process.

Another way Mack provides in-depth technical support is through Mack’s Body Builder Support team, says David Troupe, a representative of the team. Vocational trucks like this frequently have complex parameters and programming for their engine power takeoffs (PTOs), which power the hydraulics the Bronto uses to operate the aerials. Troupe and his colleagues work closely with Tim Smith of Nextran to diagnose, troubleshoot and reset parameters during the body installation process or while the truck is in operation.

“Every truck for Bronto is a custom truck,” Sessions says. “Mack’s engineers were very aggressive about getting the chassis exactly right for the application. ‘Yes we can do that, let’s do it.’ They were as excited about the product as I was. I didn’t run into one hiccup with them.”

Even if the trucks aren’t “exotic” by Mack standards, it doesn’t make them less impressive. The six-axle Granite delivered to Bronto in June has three steer axles and three drive axles, with a steerable rear drive axle for improved turning radius. It has a 295-foot aerial mounted on the chassis and will be used on Texas wind farms, where wind power companies have hundreds of towering windmills that require routine maintenance.

Mack showed its engineering versatility for another Bronto customer, NASA’s Jet Propulsion Lab in Pasadena, California, which uses its Mack to maintain giant dish antennas. Sessions asked Mack to reduce the weight of that truck by 1,500 pounds, which was accomplished by using the Mack m DRIVE^™ transmission and Mack axles instead of vendor components, Borath says.

Being the tallest has other advantages too. Skyway Lift Rentals looms over the competition as it keeps the New York City skyline in shape with a pair of Bronto-equipped Granites, one with five axles and a 230-foot aerial and the other with three axles and a 180-foot aerial. According to Skyway President Andrew Karelko, the units are used to wash and replace windows, as well as inspect and pressure wash building facades. New York requires buildings over six stories tall to be inspected every five years.

“We have work to do every day,” he says. The 230-foot-tall unit “opened a lot of doors for us. It was a big game changer that made us stand out from our competitors.”

When a truck like this is on the job, it needs to be utterly reliable with solid support. Nextran’s Sessions said that the more Bronto learned about Mack’s customer support capabilities, the more appealing the Granite and TerraPro became.

“They learned fairly quickly that we have a tremendous support structure with Mack’s Uptime Services,” including OneCall, Mack’s 24/7 roadside assistance, he says. “I order these trucks with five year/300,000 mile warranties. I wanted them to have the confidence that wherever these trucks go, we have it covered.”

An early demonstration of Mack’s dealer support, involving weekend diagnostics and repairs so the unit could be back on the job Monday, showed Bronto the value of Mack’s dealer network and deep technical support. “They found that Mack has the best product support network in North America,” Sessions says.

Pulkkinen agrees.

“If we have need of local, hands-on technical help, we get it very quickly from Nextran. Support has been very good from Nextran,” he says. “Customers already have good experience with Mack. I expect this good customer satisfaction will remain.”