Performance Authority Truck & Offroad
Owner: Justin Forty
Justin Forty has only had three jobs in his life. A shop cleanup kid, mechanic, and owner. In that order. No significant detours.
The first one started in the driveway of a rock pit in Oregon's Willamette Valley, where his grandfather Gene ran a one-man operation — loader operator, dump truck driver, everything. Gene did it all, and as soon as Justin was old enough to hold a wrench, he was out there with him. Not on the payroll. Just Grandpa time, witnessing a great role model define what a work ethic meant.
That time in the driveway led to four years of auto shop in high school, under a teacher whose only goal was simple: if you took all four years, you could walk out and get hired somewhere. No college required. Just enough knowledge to start turning wrenches and earning a paycheck.
"That was before the trade-shaming started in the high schools," Justin says.
His first real job came through that shop teacher's network. A big truck and RV facility just outside of town needed a shop cleanup kid. Justin started in October of 2000, his senior year. He was the parts runner, the shop hand, the guy who kept the floor scrubber charged and washed the foreman's truck. If the forklift needed an oil change, he got to do it.
He put in two years of that before the owner, Mike McKay, walked him over to a separate shop on the property. Mike found a little Craftsman toolbox, threw a bunch of tools in it, and asked one question.
"You want to work in the truck shop or the RV shop?"
Justin chose the RV side, and he still has that first toolbox Mike gave him in his garage today.
The RV work was broader than most people imagine. Not just camper repairs — head gaskets on Cummins engines, leaking roofs, plumbing, carpentry, appliances. Class A motorhomes, Class C's, slide-in campers. Everything in the Robin Williams movie "RV," Justin says he's seen in real life. Including the one that ended up in a lake.
While he was working days on the RV side, something was building after hours. Justin and two other guys at the shop — one of them a parts guy named Bennett — had gotten into the diesel performance world. This was the early 2000s, when the 7.3 liter Super Duty and the Duramax were brand new and nobody in their town was modifying diesel pickups. Their boss wanted nothing to do with it. So they did it on their own time.
"We were doing a truck every night," Justin says. "Monday through Friday. Full exhaust, intake, gauges, and a programmer. We could have worked weekends too. We couldn't keep up."
The writing was on the wall. The demand was there. The knowledge was there. The only thing missing was a shop of their own.
In 2008, that problem solved itself over lunch. Justin was twenty-five, had just bought his first house, and was sitting across from a local shop owner he knew. The owner was ready to retire.
"He basically slid the key across the counter and said, 'Why don't you buy it?' I'm thinking, how am I going to buy a business? He said, 'I'll carry it.'"
Justin partnered up with another guy, took over the shop, and finally got to do diesel performance during business hours. It was still like having two jobs — one turning wrenches, the other learning how to run a business — but at least it was all under one roof.
He ran that shop for nine years.
Then Bennett called. The same Bennett from the after-hours diesel days. He'd moved to Montana — his brother lived here — and he had an idea.
"Let's move to Montana and open a shop."
Between 2012 and 2017, Justin visited Helena five or six times, scoping the market. There were only two other diesel shops in town, and neither one specialized the way he wanted to. He sold his half of the Oregon business to a thirty-year employee, sold his house, and drove to Montana.
Performance Authority started in a rented shop with one garage door, no lift, and four trucks squeezed inside. Working on the ground again. Like starting over.
"But it made it nice," Justin says, "because everything in this building is paid for."
The building he's talking about is the facility he and Bennett designed and built from scratch — a clean, purpose-built diesel shop just north of town off of Montana Avenue. Bennett recently retired. Justin now owns the business, the equipment, and all the blue sky. Bennett still owns the dirt and the buildings, and Justin plans to purchase those over the next decade.
The shop runs lean. Justin handles operations and still jumps in on jobs. His wife Shanelle manages the office. "As soon as she's in here, I'm out there," he says. Their arrangement is simple: she deals with the people, he stays in the shop as much as he can.
His two technicians, Garrett and Kyler, round out the crew. Garrett is an Air Force veteran who spent three years as an aircraft mechanic at Kadena Air Base in Okinawa. Kyler came from construction, where he'd worked on bobcats, loaders, and pickups before landing at Performance Authority. Both of them were in the room during the interview, and both willingly spoke up about what work is like here.
"It's the only place I've worked that I enjoy going to," Kyler says. "I wake up and I look forward to coming here, even if it's a long day."
Justin doesn't take that for granted. He's been on the other side — working for someone older who didn't want to change, didn't want to listen, didn't want to hear feedback from the crew. He remembers what that felt like, and he runs his shop the opposite way.
"I value their input because I've been in their shoes," he says. "I've had an employer that didn't listen, and it stinks."
There's a poster people reference — the boss sitting behind a desk with a whip versus the leader out front pulling the rope. Justin identifies with the leader, and his crew confirms it. When the workload stacks up, he's not delegating from the office. He's out in the bay pre-assembling air bag kits or helping wrestle a lift kit into place.
About ninety percent of the work coming through Performance Authority is general diesel repair and maintenance. Oil changes, fuel filters, diagnostics, and the random problems that every owner eventually encounters. Twenty-five years of experience means Justin often has a good idea of what's going on after talking with a customer, but he's the first to say there's no substitute for putting it on the lift and running the proper diagnostics. Assumptions don't fix trucks. Hands-on troubleshooting does.
The other ten percent is the off-road and accessory work that first drew him into the industry: lift kits, bumpers, lights, the occasional winch install.
Justin operates by a simple truth: speed, quality, and cost — pick two, because you're rarely getting all three. He chooses quality first. Some shops profit by pushing volume — as many vehicles through the bays as possible. Justin would rather get the job done right the first time than see a comeback. He's fortunate enough to be in a position where he doesn't have to compromise. The reputation they've built keeps a steady stream of work coming through the door without chasing it.
He doesn't chase marketing either. Performance Authority dropped half its radio ads last year. It didn't change a thing. Word of mouth and reputation have carried the business since day one.
What Justin does chase is the next generation. He sponsors high school trap shooting teams and opens his shop every year for Helena High's job shadow program. He supports a military-themed car show in East Helena that funnels all its proceeds into high school shop programs across three schools — not scholarships for two kids, but consumables and supplies for every student who walks into a shop class.
"That's how I ended up where I am," Justin says. "It was because of those classes in school. If it wasn't for shop class, I wouldn't have gone to school."
The advice he gives to anyone thinking about entering the trades is the same advice Mike McKay gave him twenty-five years ago with a time card and a cleanup rag: get your foot in the door, be willing to do the work nobody else wants to do, and earn your way to the toolbox.
His old boss back in Oregon never wished him well. On Justin's last day after eight and a half years, the owner called him into the office and said: "Most entrepreneurs don't even make it through the first year."
Not good luck. Not congratulations. Just a veiled prediction.
Justin's been at it for seventeen years now. Two shops. Two states. Twenty-five years in the trade. The shop cleanup kid with the Craftsman toolbox built something that works — and he's hoping Garrett and Kyler might want to take it over someday.
"My retirement plan," he says, "is maybe these guys will stick around long enough."
He's dangling the carrot. They know about it. And when Kyler says he looks forward to coming in, even when he knows he's in for a long day — Justin knows the carrot might be working.
Gallery
Services
- Diesel Engine Repair & Maintenance
- Diesel Performance Upgrades
- Lift Kits & Suspension
- Truck & Off-Road Accessories

This business is a Homegrown Helena Founding Member.
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