The diesel repair business is under more pressure than ever.

Customers expect faster turnaround times, constant updates, and repairs done right the first time. Meanwhile, shops are battling technician shortages, rising costs, and shrinking margins.

So what actually separates a growing repair operation from one that constantly feels chaotic?

For Joe Gallaher, the answer comes down to systems, transparency, and people. Gallaher launched Gallaher Fleet Solutions with a single service truck in 2019. Today, the company operates two shops, a mobile service division, and employs about 40 people.

The business handles everything from preventative maintenance and diagnostics to engine replacements and aftertreatment repairs. But Gallaher says technical skill alone is no longer enough to run a successful operation.

Shops and mobile services must work together

Modern diesel repair businesses need more than a traditional shop setup. While shops still handle heavy repairs and technical diagnostics, mobile service units have become critical for reducing downtime and responding quickly to customers.

“Shops alone can’t handle every situation,” Gallaher explained.

Mobile units can perform on-site maintenance, emergency repairs, and inspections without forcing trucks off the road for extended periods. That balance between shop work and field service keeps workflow moving while improving customer uptime.

The goal, he says, is simple: do the right job in the right place.

Transparency matters more than most owners think

One of the biggest mistakes repair shop owners make is keeping employees in the dark about how the business operates.

Gallaher believes sharing financial information, production goals, and performance targets creates stronger teams and better accountability.

“When people understand the numbers, they stop guessing,” he said.

That includes setting measurable expectations for every role, whether it’s technician productivity targets or sales goals for service advisors. Profit-sharing programs can also help align employees with the company’s success, but only if leadership remains transparent.

“People have to trust what they’re seeing,” he said.

Hiring for attitude, training for skill

Like most diesel repair businesses, recruiting remains one of the industry’s biggest challenges. Gallaher said too many companies focus solely on technical ability instead of hiring people who fit the company culture and show a willingness to learn.

“You can teach skills,” he said. “You can’t easily fix [a] poor attitude.”

He also stressed the importance of structured onboarding and apprenticeship programs, especially as experienced technicians become harder to find. Clear documentation and repeatable processes are equally important as businesses scale.

“People forget things,” he noted. “If processes aren’t written down, consistency disappears.”

Leadership becomes the bottleneck

Growth also forces owners to confront an uncomfortable reality: sometimes they become the biggest obstacle.

Many repair shop owners struggle to delegate responsibility and step away from day-to-day firefighting. But Gallaher said scaling a business requires trusting others and having difficult conversations early.

“If something feels off, address it immediately,” he said. “Waiting only makes it worse.”

Growth requires sacrifice

Gallaher also challenged the idea that work-life balance comes easily during rapid growth phases. Building a business often demands long hours, tough decisions, and personal sacrifice, especially in the early years.

“Growth always comes with trade-offs,” he said.

The key is being honest about priorities, surrounding yourself with the right people, and clearly communicating your vision to employees.

For Gallaher, strong diesel repair operations ultimately come down to a few fundamentals: build clear systems, invest in people, communicate openly, and stay disciplined as the business grows.

“Keep it simple,” he said. “That’s how you scale without losing control.”