Theo Marsh

• Diagnose and repair Class 8 engines including Cummins, Detroit Diesel, and PACCAR, cutting average bay turnaround by approximately 18%. • Plan and complete preventative maintenance schedules for 40+ fleet units while maintaining a strong safety record. • Service EPA aftertreatment systems including DPF and SCR; document repairs and verify road-readiness. • Mentor 2 apprentices on diagnostic workflow, lockout/tagout, and quality-control inspections.

• Performed diesel engine overhauls, brake and air-system repairs, driveline service, and HD electrical diagnostics across mixed truck fleets. • Completed warranty work for OEM dealers with accurate parts, labor, and inspection documentation. • Maintained 95%+ first-time fix rate on assigned tickets through disciplined testing and root-cause diagnosis. • Coordinated road tests and final quality checks to return customer vehicles safely and on schedule.

• Completed hands-on training in diesel powertrains, hydraulic systems, brakes, and shop equipment under senior technician supervision. • Built safe inspection, measurement, and preventive-maintenance habits through structured shop rotations. • Applied OSHA-aware shop safety, lockout/tagout, and basic welding practices while supporting repair teams.

Coursework in diesel engine fundamentals, heavy-duty electrical systems, hydraulics, air brakes, diagnostics, welding basics, and fleet preventive maintenance.

ASE-certified in diesel engines, drivetrains, brakes, suspension and steering, electrical/electronic systems, preventive maintenance, and inspection.