Diesel Mechanic

Job Overview

A Diesel Mechanic is responsible for inspecting, diagnosing, repairing, and maintaining diesel-powered trucks, trailers, and heavy equipment. This role ensures fleet vehicles operate safely and efficiently by performing preventative maintenance, engine repairs, electrical diagnostics, and hydraulic system troubleshooting.

The ideal candidate has strong mechanical skills, experience with diesel engines, and knowledge of diagnostic tools. Diesel mechanics work in repair shops, fleet maintenance facilities, or as field service technicians, depending on the employer.

Key Responsibilities

Vehicle Inspection & Diagnostics

• Perform routine inspections and safety checks on trucks, trailers, and heavy equipment.
• Use diagnostic software and tools (e.g., Cummins INSITE, CAT ET, Detroit Diesel Diagnostic Link) to troubleshoot engine and system issues.
• Identify mechanical, electrical, and hydraulic failures and recommend appropriate repairs.

Repair & Maintenance Work

• Repair or replace diesel engines, transmissions, braking systems, axles, and cooling systems.
• Perform oil changes, filter replacements, and fluid top-offs as part of routine maintenance.
• Adjust, align, and replace tires, suspension components, and steering systems.
• Troubleshoot air brake systems, fuel injectors, and DEF (Diesel Exhaust Fluid) systems.
• Conduct welding and fabrication as needed for minor truck and trailer repairs.

Preventative Maintenance & Compliance

• Follow preventative maintenance schedules to reduce vehicle downtime and costly breakdowns.
• Ensure compliance with DOT (Department of Transportation) safety regulations.
• Document all repairs, services, and inspections for fleet maintenance records.

Parts Ordering & Inventory Management

• Identify necessary parts for repairs and coordinate with suppliers to order replacements.
• Maintain an inventory of filters, fluids, belts, hoses, and essential truck components.
• Keep tools and diagnostic equipment in good working condition.

Emergency Repairs & Roadside Assistance

• Provide on-call or roadside repair support for fleet breakdowns.
• Diagnose and fix electrical issues, engine failures, or air brake malfunctions on-site.
• Work with drivers and dispatch teams to minimize vehicle downtime.

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