Trade Career Comparison

Which trade career fits you best?

Diesel Mechanic

Inspect, repair, and overhaul diesel engines in trucks, buses, and heavy equipment.

$58,350/yr median

$36,850$78,110

AverageHeavyUnion: LowEntry: Low

Training Path

Trade school + OJT (1-2 years)

Environment

Indoor

Outlook

Average (+5%)

BLS Code

49-3031

Pros

✓Strong demand driven by the freight and transportation industry — trucks, buses, and heavy equipment always need maintenance.
✓Faster entry than apprenticeship-based trades — a 1-2 year trade school program plus on-the-job training gets you started.
✓Good earning potential that grows significantly with experience and manufacturer-specific certifications.
✓Variety of work environments — you can work for trucking companies, equipment dealers, municipal fleets, mining operations, or independently.
✓Skills are directly applicable to personal vehicles and side work — diesel mechanics often save thousands on their own truck and equipment maintenance.

Cons

✗Physically demanding work — diesel engines and components are large and heavy, requiring significant lifting, bending, and straining.
✗The work environment is noisy, greasy, and involves exposure to diesel exhaust, solvents, and other chemicals.
✗Shop work means standing on hard concrete floors for long hours, which takes a toll on feet, knees, and back.
✗Lower union representation than most construction trades, meaning benefits and job protections depend heavily on your employer.
✗Technology is changing rapidly with emissions systems, telematics, and hybrid/electric powertrains, requiring continuous learning.
✗On-call and road service work means responding to breakdowns at any hour, including nights and weekends.

What the Life Is Like

Diesel mechanics work in shop environments and sometimes in the field, diagnosing and repairing the engines, transmissions, brakes, and electrical systems of trucks, buses, and heavy equipment. A typical day might involve performing a scheduled service on a semi-truck, diagnosing an engine fault code using diagnostic software, rebuilding a hydraulic cylinder on an excavator, and replacing a clutch on a dump truck.

Most diesel mechanics work 40-50 hours per week. Fleet shops for trucking companies or municipalities often run multiple shifts, and you may work evenings or nights, especially early in your career. Dealership mechanics work more regular hours but face pressure to complete repairs quickly to meet flat-rate billing targets. Mobile diesel mechanics who do road calls have the most unpredictable schedules but often earn the most.

The work is hands-on and physical. Diesel components are significantly larger and heavier than automotive parts — a diesel engine can weigh over a ton. You will use hoists, jacks, and overhead cranes regularly. The diagnostic side is increasingly computerized, with modern diesel engines managed by sophisticated electronic control modules. Successful diesel mechanics combine old-school mechanical skills with the ability to navigate complex diagnostic software and wiring diagrams.

How to Get Started

Complete a diesel technology program

Community colleges and trade schools offer 1-2 year programs in diesel technology covering engine repair, fuel systems, electrical systems, brakes, and hydraulics. Programs accredited by ASE Education Foundation are preferred by employers. Hands-on shop time is critical.

Get ASE (Automotive Service Excellence) certified

ASE offers a series of medium/heavy truck certifications (T1-T8) covering different systems. Start with the most relevant to your work and build your credentials over time. ASE certification is recognized industry-wide and directly impacts your earning potential.

Start with an entry-level mechanic or helper position

Look for positions with trucking companies, equipment dealers, municipalities, or independent repair shops. Entry-level work involves oil changes, brake jobs, and tire work, but you will gradually take on more complex diagnostic and repair tasks.

Pursue manufacturer-specific training

Cummins, Caterpillar, Detroit Diesel, and other major manufacturers offer training programs and certifications. Factory training on specific engine platforms makes you more valuable and is often provided by dealers at no cost to their employees.

Advance into specialization or shop management

With experience, you can specialize in areas like electronic diagnostics, hydraulic systems, or engine overhaul. Lead mechanic, shop foreman, and fleet manager positions offer higher pay with less physical work. Some diesel mechanics open their own repair shops.

Felony Record & Licensing

Generally Accessible

ASE diesel certifications do not screen for criminal history. Many employers are reentry-friendly.

Diesel Mechanic is one of the more accessible trades for people rebuilding after a conviction.

Training Funding & Support

Pell Grants Are Available Again

As of July 2023, the FAFSA no longer asks about drug convictions. The FAFSA Simplification Act restored Pell Grant eligibility for incarcerated and formerly incarcerated students. If a past drug conviction kept you from financial aid before, you can apply again.

WIOA Workforce Funding

The Workforce Innovation and Opportunity Act (WIOA) funds free job training, career counseling, and supportive services (transportation, work clothes, childcare) for people reentering the workforce. Contact your local American Job Center (careeronestop.org) to see what's available in your area.

Ban-the-Box & Fair Chance Hiring

Over 37 states and 150+ cities have "ban-the-box" or fair chance hiring laws that prevent employers from asking about criminal history on job applications. Many require waiting until after an interview or conditional job offer. These laws are expanding rapidly — check your state's specific rules.

Licensing laws vary by state and change frequently. This is general guidance, not legal advice. Always verify with your state's licensing board before enrolling in a training program.

Data last verified March 2026 · View sources

We verify our data against official sources. Verification dates show when we last checked — they do not guarantee the information is still current. Laws, rates, and thresholds can change at any time. Always confirm critical information at the official source or with a qualified professional.

National Employment Law Project (NELP) — Fair Chance Hiring

General trade accessibility levels for people with felony convictions — categorized as generally-accessible, varies-by-state, often-restricted, or highly-restricted

https://www.nelp.org/policy-issue/criminal-records-and-employment/

Verified March 2026

trade-schools.net — Jobs for Felons

Trade accessibility and reentry employment guidance for specific trades

https://www.trade-schools.net/articles/jobs-for-felons

Verified March 2026

Hire Felons — Reentry Employment Guide

Employer reentry hiring policies and trade accessibility for people with felony convictions

https://www.hirefelons.org/

Verified March 2026

ASE — About ASE Testing

ASE (Automotive Service Excellence) certification — no criminal history screening

https://www.ase.com/certification-series/

Verified March 2026

OSHA — Powered Industrial Trucks

OSHA forklift certification — employer-provided, no criminal history screening

https://www.osha.gov/powered-industrial-trucks

Verified March 2026

EPA — Section 608 Technician Certification

EPA Section 608 refrigerant certification — no criminal history screening

https://www.epa.gov/section608

Verified March 2026

Federal Student Aid — FAFSA Simplification Act

Pell Grant eligibility restored for people with drug convictions and incarcerated individuals, effective July 1, 2023; PELL_GRANT_RESTORED_DATE: "July 2023"

FAFSA Simplification Act, Pub. L. 117-103 (2021); 20 U.S.C. § 1070a

https://studentaid.gov/announcements-events/fafsa-simplification

Verified March 2026

National Conference of State Legislatures (NCSL) — Ban the Box Legislation

Ban-the-box and fair chance hiring laws — 37+ states + DC + 150+ localities as of 2026; BAN_THE_BOX_STATE_COUNT: 37; BAN_THE_BOX_CITY_COUNT: 150

https://www.ncsl.org/labor-and-employment/ban-the-box-legislation

Verified March 2026

NELP — Ban the Box: U.S. Cities, Counties, and States

Fair chance hiring law coverage — 37+ states + DC + 150+ localities; BAN_THE_BOX_PRIVATE_EMPLOYER_STATES: ["California", "Illinois", "New Jersey", "Washington"]

https://www.nelp.org/publication/ban-the-box-fair-chance-hiring-state-and-local-guide/

Verified March 2026

U.S. Department of Labor — Reentry Employment Opportunities (REO)

WIOA Section 169 workforce funding for reentry — job training, career counseling, and supportive services

Workforce Innovation and Opportunity Act, 29 U.S.C. § 3224; WIOA Sec. 169

https://www.dol.gov/agencies/eta/reentry

Verified March 2026

Legal Information Institute — 18 U.S.C. § 922

18 U.S.C. § 922(g) — federal prohibition on felons possessing firearms, effectively barring law enforcement careers

18 U.S.C. § 922(g)(1)

https://www.law.cornell.edu/uscode/text/18/922

Verified March 2026