Custom Truck One Source (CTOS) — Union Grove, WI

A Day Building the Trucks That Keep America Working

When you step into the CTOS shop in Union Grove, your bay holds a cab-and-chassis ready to become a purpose-built workhorse. You’ll mount PTOs, plumb hydraulic circuits, route wiring harnesses, fit crane bases, and fabricate the small details that make a build truly custom. By day’s end, you’ll test systems, button up the install, and sign off on a safe, quality build that meets exact customer specs.

What You’ll Work On

• Install and integrate custom truck bodies, utility units, cranes, aerial devices, and accessories.
• Complete mechanical, hydraulic, electrical, and pneumatic installs from blueprint to final test.
• Read and execute from wiring diagrams, schematics, prints, and technical drawings.
• Mount PTOs, pumps, hose reels, hydraulic tanks and valves; wire lighting, controls, and accessories.
• Fabricate brackets, mounts, and one-off components to fit the application.
• Troubleshoot issues during the build and resolve them quickly and safely.
• Perform quality checks to ensure compliance with safety and customer requirements.
• Keep a clean, organized, and safe work area.
• Partner with production, engineering, and service teams to deliver a finished truck you’re proud of.

What You Bring

• Background as a mechanic, truck upfitter/installer, fabricator, diesel or automotive technician, or similar trade.
• Hands-on knowledge of mechanical, hydraulic, electrical, and pneumatic systems.
• Comfort using hand/power tools, diagnostic gear, and fabrication equipment.
• Ability to read blueprints, wiring diagrams, and technical manuals.
• Welding/fabrication experience is a plus.
• Strong diagnostic and problem-solving mindset.
• Ability to lift up to 50 lbs. and work in a shop environment.
• Valid driver’s license preferred.

Experience That Stands Out

• Truck equipment installation on utility or service trucks
• Construction and heavy equipment systems
• Diesel trucks, mobile cranes, and aerial devices
• Hydraulic and electrical system builds
• Fleet maintenance and DOT inspection familiarity
• Fabrication and welding
• Automotive and diesel repair

Proficiencies We Value

• Heavy Equipment Repair
• Automotive Repair
• ASE Automobile and Light Truck Certification Tests
• Lift Truck Repair & Maintenance
• Ground Support Equipment (GSE) Maintenance
• Diesel & Heavy Equipment Systems
• Hydraulic Systems & Components
• Electrical Systems & Diagnostics (Heavy Equipment)
• Crane & Lifting Equipment Systems
• DOT & Equipment Inspection Compliance
• Electrical Schematic Reading
• Equipment Installation & Wiring
• Equipment Installation

Why CTOS

• Competitive pay based on experience
• Medical, Dental, and Vision benefits
• 401(k) with company match
• Paid Time Off and holidays
• Career growth opportunities
• Stable, industry-leading organization
• Hands-on work with unique, specialized equipment

Join Custom Truck One Source and help build the specialized vehicles that power utility, telecom, construction, railroad, and infrastructure work across North America.

Apply today to become a Custom Build-Upfit Mechanic in Union Grove, WI!

Equal Opportunity Employer - EOE