Occupation · SOC 49-3031
Bus and Truck Mechanics and Diesel Engine Specialists
Diagnose, adjust, repair, or overhaul buses and trucks, or maintain and repair any type of diesel engines. Includes mechanics working primarily with automobile or marine diesel engines.
Median wage
$60,640
$41,670–$85,980
Projected growth
+2.4%
Slower than average
Annual openings
780
per year
Employed (US)
287,230
Job Zone 3
Typical preparation
Medium preparation
Stackable credential programs
483 mapped
Core skills
TroubleshootingRepairingOperations MonitoringEquipment MaintenanceQuality Control AnalysisCritical ThinkingEquipment SelectionJudgment and Decision Making
Knowledge areas
MechanicalTransportationEducation and TrainingEnglish LanguagePublic Safety and Security
Technology & tools
Computer aided design CAD softwareComputer aided manufacturing CAM softwareFacilities management softwareAnalytical or scientific softwareData base user interface and query software
Representative tasks
Use handtools, such as screwdrivers, pliers, wrenches, pressure gauges, or precision instruments, as well as power tools, such as pneumatic wrenches, lathes, welding equipment, or jacks and hoists.Inspect brake systems, steering mechanisms, wheel bearings, and other important parts to ensure that they are in proper operating condition.Raise trucks, buses, and heavy parts or equipment using hydraulic jacks or hoists.Adjust and reline brakes, align wheels, tighten bolts and screws, and reassemble equipment.Attach test instruments to equipment, and read dials and gauges to diagnose malfunctions.Perform routine maintenance such as changing oil, checking batteries, and lubricating equipment and machinery.Examine and adjust protective guards, loose bolts, and specified safety devices.Inspect, test, and listen to defective equipment to diagnose malfunctions, using test instruments such as handheld computers, motor analyzers, chassis charts, or pressure gauges.Rewire ignition systems, lights, and instrument panels.Test drive trucks and buses to diagnose malfunctions or to ensure that they are working properly.Diagnose and repair vehicle heating and cooling systems.Inspect, repair, and maintain automotive and mechanical equipment and machinery, such as pumps and compressors.Inspect and verify dimensions and clearances of parts to ensure conformance to factory specifications.Disassemble and overhaul internal combustion engines, pumps, generators, transmissions, clutches, and differential units.Adjust or repair computer controlled exhaust emissions devices.Rebuild gas or diesel engines.Specialize in repairing and maintaining parts of the engine, such as fuel injection systems.Recondition and replace parts, pistons, bearings, gears, and valves.Install or repair accessories.Repair or adjust seats, doors, or windows.Dismount, mount, and repair or replace tires.Align front ends and suspension systems.Maintain or repair vehicles with alternative fuel systems, including biodiesel, hybrid, or compressed natural gas vehicles.Measure vehicle emissions to determine whether they are within acceptable limits.Follow green operational practices involving conservation of water or energy or reduction of solid waste.Operate valve-grinding machines to grind and reset valves.
Competency framework
Skill expectations by proficiency level.
emerging
Hand tools and basic power tools — identify and use under direct supervision during routine service tasks at a commercial vehicle maintenance shop.Brake system components and steering mechanisms — inspect visually following a checklist under technician guidance in a fleet maintenance bay.Hydraulic jacks and hoists — operate to raise trucks and heavy equipment under close supervision in accordance with shop safety protocols.Brake adjustment and wheel alignment procedures — perform basic steps with direct oversight while reassembling light-duty commercial vehicle components.Test instruments and pressure gauges — attach to vehicle systems and read dials under supervisor direction to support initial malfunction diagnosis.Routine maintenance tasks — execute oil changes, battery checks, and lubrication on buses and trucks following a prescribed maintenance schedule.Protective guards, loose bolts, and safety devices — examine and report discrepancies to a lead technician during pre-trip inspection routines.Defective equipment — listen for abnormal sounds and document observations using a handheld computer under guidance from an experienced mechanic.Shop safety rules and personal protective equipment — apply consistently during all repair and maintenance activities in a vocational training or entry-level shop environment.Parts and fluid inventory — locate, retrieve, and log basic components using shop inventory management software under supervisory direction.
developing
Hand tools, pneumatic wrenches, and welding equipment — select and operate with limited oversight to complete scheduled repairs on medium-duty diesel trucks.Brake systems, wheel bearings, and steering mechanisms — inspect and evaluate independently against manufacturer specifications during scheduled preventive maintenance visits.Hydraulic hoists and floor jacks — position and operate without direct supervision to safely raise buses and heavy equipment in a busy fleet shop.Brake relining, wheel alignment, and bolt torquing — adjust and complete reassembly to specification across a range of commercial vehicle models encountered in daily workflow.Motor analyzers and chassis diagnostic charts — connect and interpret readings to isolate malfunctions on diesel engines with moderate complexity in a fleet maintenance environment.Preventive maintenance intervals — manage and document oil changes, battery load tests, and lubrication cycles for multiple vehicles using facilities management software.Safety guards and critical fasteners — systematically examine and adjust on returning fleet vehicles, escalating findings that exceed acceptable tolerances to senior staff.Diagnostic data from handheld computers and pressure gauges — analyze and cross-reference to narrow probable causes of reported drivability complaints on route buses.Repair timelines and work orders — prioritize and communicate with dispatchers and service writers to ensure on-time vehicle return in a high-volume commercial shop.Troubleshooting findings and repair recommendations — document clearly using word processing and spreadsheet software to maintain accurate vehicle service histories.
proficient
Full range of hand tools, precision instruments, and power equipment — deploy autonomously to perform complex overhauls on heavy-duty diesel engines and drivetrain systems.Brake systems, steering geometry, and suspension components — diagnose and repair comprehensively across diverse bus and truck makes and models without supervisory input.Hydraulic lifting equipment and specialized hoists — select and configure appropriately for non-standard vehicle configurations and oversized components in a large fleet facility.Multi-system reassembly including brake relining, wheel alignment, and torque sequencing — execute to manufacturer and regulatory standards on vehicles returning to revenue service.Advanced diagnostic software, motor analyzers, and analytical instruments — apply systematically to resolve intermittent or multi-system faults on electronically controlled diesel powertrains.Comprehensive preventive maintenance programs — evaluate and refine schedules for large mixed fleets, incorporating oil analysis data and manufacturer service bulletins.Safety device compliance and protective guard integrity — assess against federal and state commercial vehicle standards and authorize return-to-service decisions independently.Complex equipment malfunctions — troubleshoot using deductive reasoning and field experience to identify root causes and prevent recurrence across a fleet of transit or freight vehicles.Repair cost estimates and parts sourcing — prepare accurately using materials requirements planning and inventory software to support maintenance budgeting in a fleet operation.Technical guidance and hands-on coaching — provide to developing technicians during challenging diagnostic or repair scenarios in the shop environment.
advanced
Shop-wide maintenance strategy and quality standards — develop and enforce across all technician levels to ensure regulatory compliance and maximum fleet uptime.Diagnostic and repair competency frameworks — design and implement for the full technician team, mapping training to O*NET skill domains and industry certification requirements.Fleet maintenance technology investments — evaluate and recommend adoption of new diagnostic software, CAD/CAM tooling, and telematics systems at the organizational level.Cross-functional safety and inspection programs — lead in alignment with federal DOT and state public safety regulations, reducing out-of-service rates across the entire vehicle fleet.Complex multi-system failure investigations — direct and resolve at the fleet or enterprise level, synthesizing data from multiple diagnostic platforms and technician reports.Preventive and predictive maintenance policies — author and continuously improve using fleet performance data, driving measurable reductions in unplanned downtime and repair costs.Technician hiring, onboarding, and career development — oversee to build a high-performing maintenance team capable of servicing advanced diesel and alternative-fuel vehicles.Vendor and parts supplier relationships — manage strategically using supply chain and inventory management systems to optimize cost, quality, and parts availability for the organization.Organizational performance metrics and maintenance KPIs — establish, monitor, and present to senior leadership to drive continuous improvement in fleet reliability and cost efficiency.Industry knowledge and best practices — represent externally through participation in professional associations, technical standards committees, or apprenticeship program development.
Also known as
203 alternate job titles map to this occupation.
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