Diesel Mechanic

Kelly Professional & Industrial; Bolingbrook (IL); On-site; USD 49,593 - 59,236; Full time

Job summary

Kelly Professional & Industrial is hiring a Diesel Technician III in Bolingbrook, IL. This senior-level role demands strong diagnostic and electrical skills, with responsibilities including complex repairs and mentoring junior technicians.

Ideal candidates will have at least 5 years of experience and be proficient with OEM diagnostic tools. The position offers competitive pay of $36.00 to $43.00 per hour based on experience.

Qualifications

• Minimum 5+ years of experience in diesel truck or heavy equipment repair.
• Advanced diagnostic experience using OEM software.
• Valid driver's license required.

Responsibilities

• Diagnose and repair complex mechanical, electrical, aftertreatment, and driveline systems.
• Mentor and train Technician I and II team members.
• Conduct and verify all levels of preventative maintenance.

Skills

Advanced diagnostic experience

Electrical systems knowledge

Mentoring abilities

Understanding of aftertreatment systems

Problem-solving skills

Strong communication

Education

ASE Medium/Heavy Truck T-Series certifications or ASE Master certification

OEM-specific training or certifications

Tools

Cummins INSITE

Detroit DiagnosticLink

Navistar

Job description

Kelly Services is hiring a Diesel Technician III for a direct-hire opportunity with our client’s Truck Service Point team. This is a senior-level diesel technician role ideal for someone with advanced diagnostic experience, strong electrical and aftertreatment knowledge, and the ability to mentor other technicians in a busy shop environment.

DIRECT HIRE

Pay: $36.00 to $43.00 per hour, based on experience

Shift: 10:30am-6:30pm first 6 months, then 3:30-11pm

The Diesel Truck Technician III is 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, supporting high-quality repair standards, troubleshooting difficult issues, and helping train junior technicians.

Key Responsibilities

Advanced Diagnostics & Repair

• Diagnose and repair complex mechanical, electrical, aftertreatment, and driveline systems.
• Troubleshoot diesel engines, DPF, DOC, SCR, emissions systems, multiplexing systems, CAN bus networks, and high-level electrical faults.
• Perform engine performance testing, calibrations, and software updates using OEM diagnostic tools.
• Read and interpret wiring diagrams, schematics, service manuals, and diagnostic reports.

Major Component Repair

• Replace engine components including turbochargers, injectors, EGR systems, pumps, and related parts.
• Perform repairs and replacements on transmissions, differentials, axles, brakes, suspension, and steering systems.
• Complete advanced repairs with a focus on safety, accuracy, and quality.

Preventative Maintenance & Compliance

• Conduct and verify all levels of preventative maintenance, including PM A, B, and C inspections.
• Perform DOT inspections and ensure work meets regulatory compliance standards.
• Identify recurring fleet issues and recommend corrective actions.

Leadership & Technical Support

• Mentor and train Technician I and II team members on diagnostics, repair methods, and shop best practices.
• Serve as a technical resource for complex repair assignments.
• Support shop leadership with quality control and repair verification.

Required Qualifications

• Minimum 5+ years of experience in diesel truck or heavy equipment repair.
• Advanced diagnostic experience using OEM software such as Cummins INSITE, Detroit DiagnosticLink, Navistar, or similar tools.
• Strong understanding of electrical systems, aftertreatment systems, emissions systems, and data networks.
• Ability to read complex wiring diagrams, schematics, and service manuals.
• Valid driver’s license.
• Ability to lift 50+ lbs. and perform physically demanding work in a shop environment.

Preferred Qualifications

• ASE Medium/Heavy Truck T-Series certifications or ASE Master certification.
• OEM-specific training or certifications such as Cummins, Detroit, PACCAR, Navistar, or Allison.
• Experience training or mentoring other diesel technicians.
• Strong communication, problem-solving, and leadership skills.
• CDL Class A or B preferred.

Apply Today

Take the next step in your diesel technician career with Kelly Services. Apply today to be considered for this senior-level Diesel Technician III opportunity.