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Diesel Mechanic Job Description Template

Free diesel mechanic and technician job description templates: standard, dealership, heavy equipment, fleet, and apprentice. Download 5 as one DOCX.

Nick Anisimov

Nick Anisimov

FirstHR Founder

Hiring
15 min

Diesel Mechanic Job Description Templates

5 free templates by shop type. Download as DOCX or copy-paste.

The diesel mechanic job description is really several different postings under one title. A dealership technician working to manufacturer standards, a heavy equipment mechanic fixing hydraulics in the field, and a fleet mechanic running DOT inspections on Class 8 trucks all do the trade, but they need different skills, certifications, and licenses. Most templates online give you one generic version, which leaves a shop or fleet with a posting that misses the equipment, the pay structure, and the compliance that actually define the role.

At FirstHR, we build for the trucking, fleet, and equipment businesses that hire mechanics directly, where the owner or shop foreman writes the posting and runs the hire. The five templates below cover the role by shop type: standard, dealership/OEM, heavy equipment, fleet/trucking, and apprentice. They cover both diesel mechanic and diesel technician, since the federal data treats them as one occupation. Fill in the brackets and post. For the principles behind any posting, the guide to writing a job description covers the fundamentals.

TL;DR
Five free diesel mechanic job description templates: Standard, Dealership / OEM, Heavy Equipment, Fleet / Trucking, and Apprentice. Download all five as one DOCX. The templates cover both diesel mechanic and diesel technician. A diesel mechanic inspects, diagnoses, repairs, and maintains diesel engines and vehicles, with median pay of $60,640 (BLS, May 2024). ASE certification and, for fleet roles, a CDL are common requirements.

What Does a Diesel Mechanic Do?

A diesel mechanic inspects, diagnoses, repairs, and maintains diesel engines and the vehicles and equipment they power, from trucks and buses to construction and farm machinery. The federal data maps the role to bus and truck mechanics and diesel engine specialists (SOC 49-3031), which covers both diesel mechanic and diesel technician titles.

For the employer writing the posting, the key point is that the work depends on the shop and equipment. A dealership tech works to manufacturer standards; a heavy equipment mechanic services hydraulics and machinery; a fleet mechanic handles DOT inspections and Class 8 trucks. The five templates on this page split by shop type so the responsibilities and requirements match the actual role rather than a generic definition.

Diesel Mechanic Duties and Responsibilities

Diesel mechanic duties center on diagnosis, repair and maintenance, safety and inspection, and records. The shop type shifts the emphasis, warranty work at a dealership, hydraulics on heavy equipment, DOT inspections in a fleet, but these four categories hold across nearly every diesel mechanic role. These are the duties grouped the way the templates use them.

Diagnosis
Diagnose engine and system issues
Use diagnostic software and tools
Identify the cause, not just the symptom
Repair and maintenance
Repair and overhaul diesel engines
Perform preventive maintenance
Service brakes, drivetrains, and hydraulics
Safety and inspection
Follow shop safety procedures
Perform DOT and equipment inspections
Test vehicles to confirm repairs
Records
Keep accurate service records
Maintain required compliance records
Communicate repair needs and timelines

A strong posting grounds these in your specifics: the equipment, the pay structure, the certifications, and who the mechanic reports to. For a structured way to scope any role before posting, the guide to defining job responsibilities walks through the process.

Diesel Mechanic Skills and Requirements

A diesel mechanic needs hands-on repair skills, diagnostic ability, and the right certifications for the role. List what is truly required separately from what is preferred so you do not screen out strong, experienced candidates.

TypeWhat to look for
Hard skillsDiesel engine repair, diagnostics, brakes, drivetrains, hydraulics
Tools and softwareShop tools, diagnostic software, maintenance systems
CertificationsASE (T-series), manufacturer certification where relevant
EducationHigh school diploma minimum; vocational diesel training preferred

Most shops weigh hands-on experience and the right certifications over formal education. Require the experience and any genuinely needed certifications, and keep the rest under preferred. Keep the language neutral and inclusive too, since the EEOC prohibits job advertisements that show a preference based on protected characteristics, and the SHRM guide to writing a job description covers the standard sections.

Which Template Should You Use?

Pick the template by your shop type and the equipment you service. All five share the same skeleton, but each emphasizes the duties, certifications, and licenses that fit a specific kind of diesel role. Use this guide to choose.

Standard
Shop / general
The universal version for a repair shop or general diesel role. Diagnose, repair, and maintain diesel engines and vehicles. Includes a senior-level preset for a journeyman tech. Start here.
Dealership / OEM
Dealer service dept
For a dealership service department. Adds manufacturer (OEM) diagnostic tools, warranty work and documentation, and flat-rate or book-hour pay. Often calls for OEM certification.
Heavy Equipment
Off-highway
For construction, mining, agriculture, and equipment rental. Adds hydraulics, tracked machinery, and field service. A CDL is often not required for this version.
Fleet / Trucking
Class 8 / municipal
For trucking and municipal fleets. Adds DOT inspections, air brakes, FMCSA recordkeeping, and a CDL with air brake endorsement. Also called truck or OTR mechanic.
Apprentice / Entry-Level
Growing junior talent
For growing junior talent. No prior experience required, with vocational training preferred, structured mentorship, and a gradual certification pathway.
Start With Your Shop and Equipment
Two questions pick the template. First, what kind of operation? Dealership for OEM service work, Heavy Equipment for off-highway machinery, Fleet for trucks and DOT-regulated vehicles, or Standard for a general shop. Second, what level? Use the Apprentice template to grow junior talent, or the senior-level preset inside the Standard template for a journeyman. Then set the ASE, manufacturer, and CDL requirements to match.

5 Free Diesel Mechanic Job Description Templates

Download all five as a single Word document or copy individual templates. Each follows the same structure: company summary, position overview, key responsibilities, required and preferred qualifications, certifications and physical demands, and compensation and how to apply, with an EEO statement included. Fill in the brackets before you post.

Download All 5 Job Description Templates
Standard, dealership, heavy equipment, fleet, and apprentice. All in one DOCX.

Template 1: Standard Diesel Mechanic

The universal version for a repair shop or general diesel role, including a senior-level preset for a journeyman tech. Diagnose, repair, and maintain diesel engines and vehicles. Start here.

Diesel Mechanic Job Description (Standard)
DIESEL MECHANIC JOB DESCRIPTION
Company: __ ([City, State])
Department: Service / Shop
Reports to: [Shop Foreman / Service Manager / Owner]
Employment type: Full-time
Compensation: [Hourly / flat-rate / salary]

ABOUT [COMPANY NAME]

[One or two sentences: the kind of shop or fleet you run, the equipment you
service, and the team this person will join.]

POSITION OVERVIEW

[Company Name] is hiring a Diesel Mechanic to inspect, diagnose, repair, and
maintain diesel engines and vehicles. You will keep our equipment running safely
and reliably, working in a shop environment and following safety and quality
standards.

KEY RESPONSIBILITIES

Diagnose engine, transmission, brake, and electrical issues
Perform preventive maintenance and inspections
Repair and overhaul diesel engines and components
Use diagnostic software and shop tools
Test vehicles to confirm repairs
Keep accurate service and repair records
Follow shop safety procedures
Communicate repair needs and timelines

REQUIRED QUALIFICATIONS

High school diploma or equivalent
2+ years of diesel repair experience
Knowledge of diesel engines and systems
Own basic tools (or per shop tool policy)
Ability to lift heavy parts and stand for long shifts

PREFERRED QUALIFICATIONS

ASE certification (T-series or Master Truck Technician)
Postsecondary diesel training
CDL (Class A or B)
Senior level: 5+ years, ASE Master, mentors junior techs

CERTIFICATIONS, LICENSES, AND PHYSICAL DEMANDS

ASE: preferred [or required: _______]
CDL: [not required / preferred / required: Class __]
Able to lift up to __ lbs and work in a shop environment

COMPENSATION AND HOW TO APPLY

Pay: $____ per [hour / year] [+ benefits]
To apply, email __ with your resume.
[Company Name] is an equal opportunity employer.

Template 2: Diesel Technician (Dealership / OEM)

For a dealership service department. Adds manufacturer (OEM) diagnostic tools, warranty work and documentation, and flat-rate or book-hour pay. Often calls for OEM certification.

Diesel Technician Job Description (Dealership / OEM-Trained)
DIESEL TECHNICIAN JOB DESCRIPTION (DEALERSHIP / OEM)
Company: __ ([City, State])
Department: Service
Reports to: [Service Manager / Shop Foreman]
Employment type: Full-time
Compensation: [Flat-rate / book hours / hourly]

POSITION OVERVIEW

[Company Name] is hiring a Diesel Technician for our dealership service
department. You will diagnose and repair vehicles to manufacturer standards,
handle warranty work and documentation, and use manufacturer diagnostic tools to
keep customers' vehicles running.

KEY RESPONSIBILITIES

Diagnose and repair vehicles to manufacturer (OEM) standards
Use manufacturer diagnostic software and tools
Complete warranty repairs and required documentation
Perform scheduled and preventive maintenance
Record labor and parts per book-hour standards
Test vehicles to confirm repairs
Maintain accurate service records
Follow dealership and safety procedures

REQUIRED QUALIFICATIONS

High school diploma or equivalent
2+ years of diesel or dealership service experience
Ability to follow OEM diagnostic and repair procedures
Own basic tools (or per shop tool policy)
Comfortable with flat-rate or book-hour pay

PREFERRED QUALIFICATIONS

Manufacturer (OEM) certification or training
ASE certification (T-series)
Warranty processing experience
Brand or engine specialization

CERTIFICATIONS, LICENSES, AND PHYSICAL DEMANDS

Manufacturer certification: preferred [or required: _______]
ASE: preferred
Able to lift up to __ lbs and work in a shop environment

COMPENSATION AND HOW TO APPLY

Pay: $____ per [hour / flat-rate] [+ benefits]
To apply, email __ with your resume.
[Company Name] is an equal opportunity employer.
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Template 3: Heavy Equipment / Off-Highway Diesel Mechanic

For construction, mining, agriculture, and equipment rental. Adds hydraulics, tracked machinery, and field service. A CDL is often not required for this version.

Heavy Equipment / Off-Highway Diesel Mechanic Job Description
HEAVY EQUIPMENT DIESEL MECHANIC JOB DESCRIPTION
Company: __ ([City, State])
Department: Service / Field Service
Reports to: [Shop Foreman / Service Manager]
Employment type: Full-time
Compensation: [Hourly / salary]

POSITION OVERVIEW

[Company Name] is hiring a Heavy Equipment Diesel Mechanic to maintain and
repair off-highway equipment such as excavators, loaders, dozers, and other
machinery. You will diagnose and fix engines, hydraulics, and drivetrains in the
shop and in the field, keeping equipment ready for work.

KEY RESPONSIBILITIES

Diagnose and repair heavy equipment engines and systems
Service hydraulic systems and components
Repair tracked and wheeled machinery
Perform field service repairs on site as needed
Conduct preventive maintenance and inspections
Use diagnostic software and shop tools
Log work in a maintenance system (CMMS)
Follow safety procedures in shop and field

REQUIRED QUALIFICATIONS

High school diploma or equivalent
2+ years repairing heavy or off-highway equipment
Strong hydraulics and diesel engine knowledge
Own basic tools (or per shop tool policy)
Ability to do physical, field-based work

PREFERRED QUALIFICATIONS

ASE or equipment manufacturer certification
Field service experience
Welding or fabrication skills
Experience with your specific equipment types

CERTIFICATIONS, LICENSES, AND PHYSICAL DEMANDS

ASE or OEM certification: preferred
Driver's license required; CDL a plus for equipment transport
Able to lift heavy parts and work outdoors in varied conditions

COMPENSATION AND HOW TO APPLY

Pay: $____ per [hour / year] [+ benefits]
To apply, email __ with your resume.
[Company Name] is an equal opportunity employer.

Template 4: Fleet Diesel Mechanic (Trucking / Municipal)

For trucking and municipal fleets. Adds DOT inspections, air brakes, FMCSA recordkeeping, and a CDL with air brake endorsement. Also called truck or OTR mechanic.

Fleet Diesel Mechanic Job Description (Trucking / Municipal)
FLEET DIESEL MECHANIC JOB DESCRIPTION
(Also called: Truck Mechanic, OTR Mechanic, Class 8 Mechanic)
Company: __ ([City, State])
Department: Fleet Maintenance
Reports to: [Fleet Manager / Shop Foreman]
Employment type: Full-time
Compensation: [Hourly / salary]

POSITION OVERVIEW

[Company Name] is hiring a Fleet Diesel Mechanic to maintain and repair our
fleet of trucks and vehicles. You will keep the fleet safe, compliant, and on
the road, performing DOT inspections, diagnosing and repairing issues, and
keeping accurate maintenance records.

KEY RESPONSIBILITIES

Maintain and repair Class 8 and fleet vehicles
Perform DOT inspections and document them
Service air brakes, engines, and drivetrains
Diagnose and repair issues to keep trucks running
Track and maintain FMCSA-required records
Perform preventive maintenance on schedule
Minimize downtime and turn vehicles around quickly
Follow shop and DOT safety procedures

REQUIRED QUALIFICATIONS

High school diploma or equivalent
2+ years of fleet or truck repair experience
Knowledge of DOT inspection requirements
Own basic tools (or per shop tool policy)
Ability to lift heavy parts and stand for long shifts

PREFERRED QUALIFICATIONS

ASE certification (T-series, including T8 PMI)
CDL Class A or B with air brake endorsement
FMCSA recordkeeping experience
Experience with your fleet's vehicle types

CERTIFICATIONS, LICENSES, AND PHYSICAL DEMANDS

ASE: preferred
CDL: [preferred / required: Class __, air brake endorsement]
Note: techs who hold a CDL and are on call for safety-sensitive
functions may be subject to DOT drug and alcohol testing (49 CFR Part 382)
Able to lift up to __ lbs and work in a shop environment

COMPENSATION AND HOW TO APPLY

Pay: $____ per [hour / year] [+ benefits]
To apply, email __ with your resume.
[Company Name] is an equal opportunity employer.

Template 5: Apprentice / Entry-Level Diesel Mechanic

For growing junior talent. No prior experience required, with vocational training preferred, structured mentorship, and a gradual certification pathway.

Apprentice / Entry-Level Diesel Mechanic Job Description
APPRENTICE / ENTRY-LEVEL DIESEL MECHANIC JOB DESCRIPTION
Company: __ ([City, State])
Department: Service / Shop
Reports to: [Shop Foreman / Senior Technician]
Employment type: Full-time
Compensation: [Hourly], mentorship provided

POSITION OVERVIEW

[Company Name] is hiring an Apprentice Diesel Mechanic to learn the trade while
supporting our shop. You will assist experienced technicians, perform basic
maintenance, and build your skills and certifications over time. This is a
strong entry point into a diesel mechanic career.

KEY RESPONSIBILITIES

Assist senior technicians with repairs
Perform basic maintenance and inspections under guidance
Learn diagnostic tools and shop procedures
Keep the shop and tools clean and organized
Help with preventive maintenance tasks
Document work as instructed
Follow shop safety procedures
Build skills toward certification

REQUIRED QUALIFICATIONS

High school diploma or equivalent
Interest in diesel mechanics and willingness to learn
Mechanical aptitude
Reliable and able to follow instructions
Able to lift parts and stand for long shifts

PREFERRED QUALIFICATIONS

Vocational or trade school training in diesel or automotive
Some hands-on or shop experience
Working toward ASE certification

CERTIFICATIONS, LICENSES, AND PHYSICAL DEMANDS

No prior certification required; cert pathway provided
Driver's license preferred
Able to lift up to __ lbs and work in a shop environment

COMPENSATION AND HOW TO APPLY

Pay: $____ per hour [+ benefits]
To apply, email __ with your resume.
[Company Name] is an equal opportunity employer.
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ASE Certifications for Diesel Mechanics

ASE certification is the most recognized credential in the field, and the Medium and Heavy Truck (T-series) set is the one most relevant to diesel mechanics. List it as preferred for most roles, and as required only where the work truly depends on it.

ASE areaCovers
T2 Diesel EnginesDiesel engine diagnosis and repair
T3 Drive TrainClutch, transmission, driveline
T4 BrakesAir and hydraulic brake systems
T6 Electrical / ElectronicElectrical and electronic systems
T8 PMIPreventive maintenance inspection

The full T-series runs from T1 through T8, with an L2 specialist credential for electronic diesel engine diagnosis, and ASE certifications require periodic recertification to stay current. See the ASE test series for the full list. For dealership roles, manufacturer (OEM) certification often matters as much as ASE.

CDL and DOT Requirements

For fleet and trucking operations, federal rules can affect both who you hire and how you onboard them. Whether a CDL and DOT testing apply depends on the specific role.

When DOT Testing Can Apply to a Mechanic
Under Federal Motor Carrier Safety Administration rules (49 CFR Part 382), drug and alcohol testing applies to employees who perform safety-sensitive functions requiring a CDL. A mechanic who holds a CDL and is on call to perform safety-sensitive functions, such as moving or test-driving commercial vehicles, can be subject to testing. Because this turns on the specific role, confirm whether it applies to your position and review the FMCSA guidance or consult a qualified advisor if unsure.

The fleet template includes CDL and DOT fields so you can set the requirement to match the work. Settle this before you post, since it affects the offer, the consent forms, and the onboarding.

How to Write a Diesel Mechanic Job Description

A strong diesel mechanic posting takes about fifteen minutes once you settle the shop type, the responsibilities, the certifications, and the pay structure. Here is the process the templates are built around. If you are building out your team, the small business hiring guide covers the steps around the posting itself.

1
Pick the shop type
Standard, dealership/OEM, heavy equipment, fleet, or apprentice, matched to your business and the equipment you service.
2
Write the real responsibilities
List the actual diagnosis, repair, safety, and recordkeeping work for your equipment, not generic filler.
3
Set certification and license requirements
Decide whether ASE, manufacturer certification, or a CDL is required or preferred, and whether DOT testing applies.
4
State the pay structure
Say whether the role is hourly, flat-rate, or salary, include a range, and add an equal opportunity statement.
5
Plan a fast hire-to-onboard process
Set up the tool policy, safety, and any DOT forms so you can onboard and track credentials cleanly once you hire.

Diesel Mechanic Pay

Diesel mechanic pay varies by experience, certification, region, and shop type, and the role is often paid hourly, flat-rate, or by salary. The federal data gives a solid anchor for setting a range.

Diesel Mechanic Pay Anchor (BLS)
Diesel service technicians and mechanics had a median annual wage of $60,640 in May 2024 (about $29.15 per hour; 10th percentile $41,670; 90th percentile $85,980). They held about 319,900 jobs, with employment projected to grow 2 percent from 2024 to 2034 and about 26,500 openings projected each year (U.S. Bureau of Labor Statistics).

Experienced, ASE-certified technicians and those at dealerships or specialized fleets tend to earn toward the higher end, while apprentices start lower. These are the most recent confirmed federal estimates for the occupation.

RoleRelative payCommon pay structure
Apprentice / entry-levelLower endHourly
Standard / shopAround the medianHourly or flat-rate
Dealership / OEMMid to higherFlat-rate or book hours
Senior / journeymanHigherHourly or salary

For setting pay, use the federal median as a reference, decide your pay structure, factor in certifications and local rates, and state the range and structure in the posting, since a growing number of states require a range.

Hiring a Diesel Mechanic

A large dealer network or carrier hires mechanics through a recruiting team and a standard pay plan. A small shop, fleet, or equipment business makes the same hire directly, and has to handle the equipment fit, the certifications, and the DOT picture itself. Here is how to do it well.

Match the template to your shop and equipment
Diesel mechanic covers very different work depending on where it happens. A dealership technician working to manufacturer standards on warranty jobs, a heavy equipment mechanic fixing hydraulics on excavators in the field, and a fleet mechanic running DOT inspections on Class 8 trucks all share the trade but need different skills and certifications. A generic template misses the equipment, the pay structure, and the licensing that define your role, which means it attracts the wrong applicants. Start from the version that matches your business, standard shop, dealership, heavy equipment, fleet, or apprentice, so the responsibilities, certifications, and pay all describe the real job, and use the standard version as a baseline when none fits exactly. Naming the equipment you service and your pay structure up front is what gets experienced techs to take a posting seriously.
Know when DOT testing and CDL rules apply
For trucking, municipal, and other fleet operations, federal rules can reach the shop, not just the cab. A mechanic who holds a CDL and is on call to perform safety-sensitive functions can be subject to DOT drug and alcohol testing under the Federal Motor Carrier Safety Administration rules, so the posting and your hiring process should account for it where it applies. The fleet template flags this directly. Decide before you post whether the role requires a CDL, whether DOT testing applies, and what certifications you expect, since these affect the job description, the offer, and the onboarding. Getting the compliance picture right up front, rather than discovering it after the hire, protects a small operation that does not have a dedicated compliance team to catch it later.
Plan certification tracking and onboarding before you post
Diesel roles come with credentials that expire and records you have to keep, so plan for them before the hire. ASE certifications need periodic recertification, a DOT medical examiner certificate is valid for a limited period, and drug and alcohol testing records must be retained under federal rules. Beyond the usual offer letter, I-9, tax forms, and state new-hire reporting, a diesel hire often involves a tool policy, a safety and PPE acknowledgement, and, for fleet roles, DOT consent forms and copies of the CDL and medical card. A small shop or fleet benefits from a simple, repeatable way to collect the right signed documents, assign safety training, and track certification and medical expiration dates, rather than rebuilding that process and risking a lapsed credential for every hire.

After You Hire: Onboarding a Diesel Mechanic

Diesel mechanic onboarding often involves more documents and compliance than a typical hire. The basics come first: the offer with the pay structure stated, the I-9, tax forms, and state new-hire reporting, plus a tool policy and a shop safety and PPE acknowledgement. For fleet and trucking roles, that can also include DOT drug and alcohol testing consent and copies of the CDL and medical card. Then comes role-specific onboarding: shop safety training, diagnostic and tool setup, and bay and systems access. For the broader flow, the new hire paperwork guide covers the documents and the training new employees guide covers running orientation with sign-offs.

The documents around the hire follow the usual sequence: the offer letter template for the terms and pay structure and the onboarding checklist template for the first weeks of setup and training.

FirstHR fits this directly: e-signature for the offer, tool policy, and safety and consent forms, document management for ASE and manufacturer certifications, CDL and DOT medical cards, and testing records, with expiration reminders so credentials do not lapse, training assignments with completion records for shop and safety onboarding, an HRIS with an org chart for your shop hierarchy, and a self-service portal where techs update certifications. Applicant tracking is coming soon to FirstHR; today the platform handles onboarding and document tracking once the candidate signs.

Key Takeaways
Diesel mechanic and diesel technician are the same federal occupation, so write for both and split instead by shop type and equipment.
Match the template to your operation: standard, dealership, heavy equipment, fleet, or apprentice, each with different certifications and licenses.
List ASE as preferred for most roles and required only where the work depends on it; manufacturer certification matters most at dealerships.
A CDL is often needed for fleet roles but not for shop or heavy equipment roles, so set the requirement to match the work.
A CDL-holding mechanic on call for safety-sensitive functions can be subject to DOT testing under FMCSA rules, so check before you hire.
Diesel mechanics had a median wage of $60,640 in May 2024, paid hourly, flat-rate, or salary depending on the shop.

Frequently Asked Questions

What is the difference between a diesel mechanic and a diesel technician?

The two titles are largely interchangeable, and the federal government tracks them as a single occupation: diesel service technicians and mechanics. In everyday use, some employers favor diesel technician for roles that lean heavily on computer diagnostics and manufacturer systems, especially at dealerships, while diesel mechanic is the more traditional term for hands-on repair work. There is no firm line between them, and many job postings use them as synonyms. For hiring, what matters more than the title is describing the actual work: the equipment serviced, the diagnostic tools used, the certifications expected, and the pay structure. The templates on this page cover both terms and split instead by the kind of shop and equipment, standard, dealership, heavy equipment, fleet, and apprentice, since that is what really changes the role.

Do I need ASE certification to hire a diesel mechanic?

No, ASE certification is not legally required to hire or work as a diesel mechanic, but it is the most widely recognized certification in the field and a strong signal of skill. ASE offers a Medium and Heavy Truck (T-series) set of certifications covering areas like diesel engines, brakes, drivetrain, electrical systems, and preventive maintenance inspection, and ASE certifications require periodic recertification to keep technicians current. For most shops, listing ASE as preferred rather than required is the right call, since it lets you consider strong, experienced mechanics who have the skills but not the certificate, while still signaling that you value it. For dealership roles, manufacturer (OEM) certification often matters as much as or more than ASE. Decide which certifications are genuinely required for your role versus preferred, and say so clearly in the posting.

Is a CDL required for a diesel mechanic?

It depends on the role. Many diesel mechanic jobs do not require a commercial driver's license, especially shop-based and heavy equipment roles where the mechanic does not drive commercial vehicles on public roads. For fleet and trucking roles, a CDL is often preferred or required, because the mechanic may need to test-drive or move Class 8 trucks, and an air brake endorsement is commonly expected. State whether a CDL is required, preferred, or not needed for your specific role, since requiring one unnecessarily shrinks your candidate pool, while leaving it out of a role that genuinely needs it attracts applicants who cannot do part of the job. The fleet template on this page includes CDL and endorsement fields so you can set the requirement to match the work.

Are diesel mechanics subject to DOT drug and alcohol testing?

They can be, depending on the role and the operation. Under Federal Motor Carrier Safety Administration rules (49 CFR Part 382), drug and alcohol testing applies to employees who perform safety-sensitive functions requiring a commercial driver's license. A mechanic who holds a CDL and is on call to perform safety-sensitive functions, such as moving or test-driving commercial vehicles, can be subject to testing when on call and ready to be dispatched. Shop-only mechanics who do not hold a CDL or perform those functions generally are not. Because the rules turn on specific facts about the role and the operation, you should determine whether they apply to your position and consult the FMCSA guidance or a qualified advisor if you are unsure. The fleet template flags this so it is considered before you hire, and FirstHR can store the related consent forms and records once the rules apply.

How much does a diesel mechanic make?

According to the Bureau of Labor Statistics, the median annual wage for diesel service technicians and mechanics was $60,640 in May 2024, which works out to about $29.15 per hour, with the lowest 10 percent earning under about $41,670 and the highest 10 percent over $85,980. Pay varies by experience, certification, region, and the type of shop, and diesel mechanics are often paid in one of several ways: hourly, flat-rate (paid per job by book hours), or salary, particularly at dealerships. Experienced ASE-certified technicians and those at dealerships or specialized fleets tend to earn toward the higher end, while apprentices and entry-level mechanics start lower. For setting pay, use the federal median as a reference, decide your pay structure, factor in certifications and local market rates, and state the range and structure clearly in the posting, since a growing number of states require a pay range.

What is the difference between a journeyman and an apprentice diesel mechanic?

An apprentice diesel mechanic is an entry-level worker learning the trade, typically with little or no prior experience, who works under the supervision of experienced technicians while building skills and certifications over time. A journeyman diesel mechanic is a fully qualified, experienced technician who can work independently across a wide range of repairs, often with several years of experience and ASE certification, and who may supervise or mentor apprentices. The progression usually runs from apprentice to mid-level mechanic to journeyman, sometimes to an ASE Master Technician or shop foreman. For hiring, this page covers both ends: the apprentice template is built for growing junior talent with mentorship and a certification pathway, while the standard template includes a senior-level preset for a journeyman role with more experience and leadership of junior techs.

What happens after I hire a diesel mechanic?

Once the candidate accepts, the hire moves into onboarding, which for a diesel mechanic often involves more documents and compliance than a typical role. The first steps are the offer and paperwork: the offer letter with the pay structure stated (hourly, flat-rate, or salary), the I-9, tax forms, and state new-hire reporting, plus a tool policy and a shop safety and PPE acknowledgement. For fleet and trucking roles, that can also include DOT drug and alcohol testing consent and copies of the CDL and medical card. Then comes role-specific onboarding: shop safety training, diagnostic and tool setup, and bay and systems access. FirstHR fits this directly: e-signature for the offer, tool policy, and safety and consent forms, document management for ASE and manufacturer certifications, CDL and DOT medical cards, and testing records, with expiration reminders so credentials do not lapse, training assignments with completion records for shop and safety onboarding, an HRIS with an org chart for your shop hierarchy, and a self-service portal where techs update certifications. Applicant tracking is coming soon to FirstHR; today the platform handles onboarding and document tracking once the candidate signs.

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