Diesel Mechanic

The County Materials Family of Companies manufactures and delivers concrete construction products to meet the demand for growing communities. Since 1946, we've relied on our talented and dedicated team members to provide reliable products with personalized service.


We're hiring a Mechanical Technician to join County Materials in St. Louis, MO

Job Summary:

We are seeking a Mechanical Technician with strong experience in diesel engines and heavy-duty equipment to maintain, troubleshoot, and repair trucks and large machinery. This role is critical to ensuring safe, reliable, and DOT-compliant operation of fleet and equipment assets.

The Mechanical Technician performs mechanical, hydraulic, pneumatic, and engine diagnostics and repairs, completes preventative maintenance and DOT inspections, and responds to emergency or unscheduled breakdowns to minimize downtime. By interpreting technical manuals, documenting repairs, maintaining clean work environments, and supporting special projects, this position plays a key role in maintaining production schedules and upholding safety and quality standards.

Job Duties & Responsibilities:

• Troubleshoot, diagnose, and repair diesel engines, trucks, and heavy-duty equipment
• Perform mechanical, hydraulic, and pneumatic repairs as needed
• Complete preventative maintenance (PMs) and DOT inspections
• Respond to emergency and unscheduled equipment breakdowns to reduce downtime
• Read and interpret technical manuals, schematics, and service documentation
• Operate, maintain, and inspect shop tools and equipment
• Follow all safety procedures, regulatory requirements, and quality standards
• Accurately document repairs, inspections, and maintenance activities
• Support team operations and assist with special projects or tasks
• Use hand and power tools, material handling equipment, welders, and cutting torches
• Maintain a clean, organized, and safe work area
• Perform other related duties as assigned

COUNTY Core Competencies: The expected behaviors of all COUNTY team members that align with Our Values and Our Commitments:

• Integrity & Organizational Awareness
• Customer First Focus
• Results Driven Orientation
• Teamwork, Safety & Collaboration
• Problem Solving & Decision Making
• Creativity & Innovation

Job-Based Competencies:

• Diesel, Mechanical, & Pneumatic Systems Knowledge
• Diagnostics & Troubleshooting
• Preventative Maintenance & Reliability
• Work Planning & Documentation
• Tool Usage
• Welding
• Communication
• Attention to Detail

Experience & Qualifications: (Required or Preferred)

• High School Diploma or Equivalent
• Minimum of 2 years' experience in diesel mechanics.
• Pro-active, multi-tasked, self-motivated team player and positive attitude.
• Strong hydraulic, mechanical, welding experience
• A valid driver's license and good driving record is required.
• CDL preferred

Work Environment:

• Work is typically performed in an Indoor , Outdoor , Field , environmentincluding extreme hot or cold temperature in confined areas
• Exposure may include: Noise, weather, machinery, chemicals
• Travel required as needed
• Typical work hours/shifts: 1st shift, overtime expectations mandatory

Physical & Work Expectations:

An individual in this position must be able to successfully perform the essential duties and responsibilities listed above. Reasonable accommodation may be made to enable individuals with disabilities to perform the essential functions of this position.
• Frequent standing, walking, bending, reaching, or handling materials/equipment.
• Occasional climbing, kneeling, or lifting/moving up to 75 pounds.
• Follow detailed instructions, communicate effectively, and safely perform job duties.
• May require the operation of specific tools, equipment, or vehicles associated with the position.

The County Materials Family of Companies connects candidates with rewarding careers in concrete manufacturing, an industry that's growing faster than most. We work alongside individuals to leverage their skills and align them with diverse job opportunities in production, transportation, safety, finance, human resources, information technology, marketing, risk management, and more.


Military service members and veterans are encouraged to apply.


Benefits Overview:


Central Processing Corporation is the payroll and benefit service of the County Materials Family of Companies.

• Health, dental and vision insurance
• Paid Short-term & Long-term disability
• 401(k) match
• 8 Paid holidays
• Paid Time Off
• Referral rewards program
• Wellness program with rewards
• Flexible Savings Options
• Employee Assistance Program
• Paid Life Insurance
• $200 Boot Allowance
• Safety focused: GUARD for Life
• Voluntary critical illness & accident insurance
• Optional Uniform Program

2026 Benefits at a glance - English

County Materials Family of Companies is an EEO/Affirmative Action Employer; all qualified applicants will receive consideration for employment without regard to any characteristic prohibited by federal, state and/or local laws.


We participate in E-Verify to confirm employment eligibility for all new hires.