Senior Diesel Technician: Advanced Diagnostics & Leadership

Unlimited Carrier Inc; Illinois; On-site; USD 52,000 - 59,000; Full time

Job summary

Unlimited Carrier Inc is seeking a senior Diesel Technician III to diagnose and repair diesel-powered trucks and equipment. You will lead and mentor junior technicians, ensuring high-quality repairs and compliance with safety standards.

You will perform advanced diagnostics, component replacements, PMs, and documentation, while coordinating with shop leadership and ensuring efficient maintenance workflows. This role requires physical fitness and strong problem-solving in a shop setting.

Qualifications

• Minimum of 5 years of experience in diesel truck or heavy equipment repair.
• Advanced diagnostic skills using OEM software such as Cummins INSITE, Detroit DiagnosticLink, and Navistar Service Software.
• Strong understanding of electrical systems, aftertreatment systems, and vehicle data networks.
• Ability to read and interpret complex wiring diagrams, schematics, and service manuals.
• Valid driver's license.
• Ability to lift 50+ pounds and perform physically demanding work.

Responsibilities

• Perform expert-level diagnostics on mechanical, electrical, aftertreatment, and driveline systems.
• Troubleshoot and repair: diesel engines, aftertreatment and emissions systems, CAN bus systems, high-level electrical faults, transmission and driveline components.
• Conduct engine performance testing, calibrations, and software updates using OEM diagnostic tools.
• Perform engine component replacement, including turbochargers, injectors, EGR systems, and pumps; replace major assemblies like transmissions, differentials, axles; execute brake, suspension, and steering repairs.
• Conduct and verify all levels of preventative maintenance (PM A, B, and C), including advanced inspection points and DOT inspections.
• Mentor and train Technicians I and II; serve as a technical resource and support shop leadership in quality control.
• Document repairs, diagnostics, and parts usage in maintenance systems; contribute to SOP improvements.
• Lead by example in following safety protocols and PPE; ensure proper use and care of tools and devices.

Skills

Diesel diagnostics

Electrical systems

Wiring diagrams

Driver's license

Physical ability

Education

ASE Certifications

Diesel technology education

Tools

Cummins INSITE

Detroit DiagnosticLink

Navistar Service Software

Job description

Unlimited Carrier Inc is seeking a senior Diesel Technician III to diagnose and repair diesel-powered trucks and equipment. You will lead and mentor junior technicians, ensuring high-quality repairs and compliance with safety standards.

You will perform advanced diagnostics, component replacements, PMs, and documentation, while coordinating with shop leadership and ensuring efficient maintenance workflows. This role requires physical fitness and strong problem-solving in a shop setting.