About JNM HD
Southern Ontario's Mobile Heavy-Duty Truck Repair Specialists
We built this business on honest work, straight talk, and showing up when you need us. No upsells. No runaround. Just quality repairs done right.
Our Story
Who We Are
JNM HD Commercial Repairs is a mobile heavy-duty truck repair company serving fleet operators and owner-operators across Southern Ontario. We specialize in diesel engine repair, engine diagnostics, brake service, aftertreatment systems, electrical diagnostics, and preventive maintenance programs — including emergency roadside repairs when you need us most.
Unlike a shop, you're not dealing with a service writer who relays messages to a mechanic you never meet. With JNM HD, you speak directly with the technician doing the work — no middleman, no miscommunication, no surprises on the invoice.
Whether you run one truck or a full fleet, you get the same level of service: experienced technicians, honest assessments, and work you can count on.
Our Approach
How We Work
Honest Assessments
We tell you what's wrong and what it'll take to fix it — nothing more. No unnecessary repairs, no inflated estimates.
We Come to You
Mobile service means no towing, no shop wait times, and no disruption to your operation. We work around your schedule.
Quality Workmanship
We take pride in doing the job right. Every repair is done properly, with the right parts, by experienced technicians.
Responsive & Reliable
When you call, we answer. When we say we'll be there, we show up. Reliability is the foundation of every fleet relationship we build.
Expertise
What We Know
Our technicians have hands-on experience with all major heavy-duty truck brands and engine platforms.
Where We Work
Where We Operate
We provide mobile heavy-duty truck repair and fleet maintenance services across Southern Ontario. Whether you're on the highway, at a job site, or at your yard — if you're in Southern Ontario, we can get to you.
Let's Talk About Your Trucks
Whether it's an emergency repair or a fleet maintenance program, we're ready to help.