Mobile Service Truck - Available 24 / 7: Big rigs don’t always break down at convenient times, and rarely at handy locations. Tractors and trailers don’t necessarily need to be diagnosed or repaired in-shop. Our well-equipped, diagnostic and repair truck can be mobile within minutes. Yes, even in the night or on Sunday afternoon. When your call comes in, a journeyman H.D. Technician will hit the road with the diagnostic equipment, tools and the skill to get you going in as short of a time as possible.