Diesel Technician III

Unlimited Carrier IncBolingbrook, IL
$36 - $43Onsite

About The Position

The Diesel Truck Technician III is a highly skilled, senior-level technician responsible for performing complex diagnostics and advanced repairs on diesel-powered trucks and related equipment. This role serves as a technical expert within the shop, providing leadership, mentoring junior technicians, and ensuring high-quality repair standards.

Requirements

  • 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+ lbs. and perform physically demanding work.

Nice To Haves

  • Formal diesel technology education or equivalent hands-on experience.
  • Multiple ASE Medium/Heavy Truck (T-Series) certifications or ASE Master Certification.
  • OEM-specific training or certifications (Cummins, Detroit, PACCAR, Navistar, Allison).
  • Experience training or mentoring other technicians.
  • Strong communication and leadership skills.
  • CDL Class A or B license.

Responsibilities

  • Perform expert-level diagnostics on complex mechanical, electrical, aftertreatment, and driveline systems.
  • Troubleshoot and repair diesel engines, aftertreatment and emissions systems (DPF, DOC, SCR), multiplexing and CAN bus systems, high-level electrical faults and communication issues, and 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 such as transmissions, differentials, and axles.
  • Execute advanced brake, suspension, and steering repairs.
  • Conduct and verify all levels of preventative maintenance (PM A/B/C), including advanced inspection points.
  • Perform DOT inspections and ensure full regulatory compliance.
  • Identify root causes of recurring fleet issues and recommend corrective actions.
  • Mentor and train Technicians I and II on best practices, troubleshooting, and repair procedures.
  • Serve as a technical resource for complex job assignments.
  • Support shop leadership in quality control initiatives.
  • Document repairs, diagnostics, and parts usage accurately in maintenance systems.
  • Contribute to procedural improvements and standard operating practices.
  • Lead by example in following all safety protocols and PPE requirements.
  • Identify hazards and take corrective action to maintain a safe work environment.
  • Ensure proper use and care of shop tools, equipment, and diagnostic devices.

Benefits

  • Pay Range: $36.00 – $43.00 per hour, based on experience, certifications, and shift.
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