Senior Diesel Technician – Fleet & Heavy Equipment Systems

CTOS - Trucks & Equipment; Fort Worth (TX); On-site; USD 60,000 - 90,000; Full time

Benefits offered by this job

Paid vacation

Sick time

Holidays

401(k) match

Healthcare

Dental

Vision

Prescription coverage

Uniforms provided

Boot allowance

Ongoing training

Job summary

Custom Truck One Source is seeking an experienced diesel mechanic for Class 6–8 trucks. You will diagnose faults with OEM software, perform repairs across chassis, PTOs, hydraulics, emissions, and electrical systems, and document findings for customers.

Qualifications include a valid driver’s license and CDL preferred, with emphasis on safety and quality. This is an on-site shop role offering competitive pay and benefits, in a team-focused environment.

Qualifications

• Proven diesel mechanic experience on heavy trucks (Class 6–8).
• Strong diagnostic and repair skills across mechanical, hydraulic, electrical systems.

Responsibilities

• Perform full-lifecycle assessment of assigned utility trucks and equipment.
• Diagnose faults using OEM software and test equipment.
• Repair chassis, PTOs, hydraulics, emissions systems, and electrical circuits.
• Document findings and order parts, then finalize quality checks for customers.

Skills

Diesel mechanics

Troubleshooting

Shop safety

CDL preferred

Education

Vocational/technical school

Tools

OEM diagnostic software

Electrical test equipment

Wiring diagrams/schematics

Job description

Custom Truck One Source (CTOS) has spent more than three decades building a nationwide footprint—40+ locations, 2,600 employees, and a 10,000+ unit fleet supporting utility, telecom, rail, and construction customers. Step into our shop and into a day defined by complex diagnostics, hands-on problem solving, and the satisfaction of putting mission-critical equipment back to work.Your DayYou’ll begin with a full-lifecycle assessment of assigned utility trucks and specialty heavy equipment—reviewing work orders, scanning for fault codes, and planning repairs. From there, you’ll move between bays tackling chassis rebuilds, PTO/hydraulic fixes, emissions maintenance, and electrical troubleshooting. You’ll document findings, order needed parts, and wrap the day with a final quality check and clear notes for customers and teammates.What You’ll Work OnAdvanced Diagnostics & Troubleshooting: Use OEM-level software and test equipment to pinpoint mechanical, hydraulic, and electronic faults.Chassis & Powertrain Repair: Inspect, repair, and rebuild chassis components, steering, suspension, and braking systems on Class 6–8 trucks.Emissions Systems: Service and repair critical emissions components with emphasis on EGR systems, coolers, and valves.PTO & Hydraulics: Troubleshoot, install, and repair PTO gearboxes and integrated hydraulic systems (pumps, cylinders, valves, winches).Electrical Systems: Read schematics to diagnose and repair complex 12V/24V circuits, wiring harnesses, starting/charging systems, and electronic control modules.What You BringValid driver’s license; CDL is a plus.Proven experience as a diesel mechanic on Class 6, 7, or 8 heavy trucks.High mechanical aptitude and an unwavering commitment to shop safety and compliance.Vocational/technical school graduates and military veterans with specialized mechanical training are strongly encouraged to apply.Why CTOSWe invest in you so you can invest in your craft. Expect competitive pay aligned to your skills and experience, paid vacation, sick time, and holidays, a 401(k) match, healthcare, dental, vision, prescription coverage, uniforms, a boot allowance, ongoing training, and more.Equal Opportunity Employer