Diesel Mechanic Tools: 125+ Essential Items for Your Toolkit

Good diesel mechanic work requires high-quality diesel mechanic tools.

If you're looking to build the industry skills employers are looking for, you need to get a diesel mechanic tool set with the essentials and start training.

Once you do, you can train to develop your skills the right way and eventually apply for entry-level diesel roles as a qualified technician.

Keep reading for our diesel mechanic tool list, informed by some of the biggest diesel brands in the world. Once you’re in school, you can start adding to your tool list for diesel mechanics to be better prepared for what's to come.

Why Is it Important for Diesel Mechanics To Have the Right Tools on Hand?

Having the right tools is essential for diesel mechanics to perform their jobs effectively and efficiently. Proper tools not only enhance productivity but also ensure safety, prevent damage and maintain professionalism in the industry. Here’s why having the right tools is crucial:

Efficiency and productivity

Using the correct tools allows diesel mechanics to complete repairs and maintenance tasks faster, reducing downtime and increasing overall workflow efficiency.

Safety

The right tools help mechanics work safely by minimizing risk of injuries caused by improper equipment use or makeshift solutions.

Damage prevention

Precision tools prevent unnecessary damage to engine components, reducing costly repairs and ensuring vehicles remain in optimal condition.

Professionalism and credibility

Equipping yourself with the right tools demonstrates knowledge and professionalism, building trust with employers and clients.

Adaptability to different diesel systems

Diesel engines vary across industries, and having specialized tools ensures mechanics can work on a wide range of systems with confidence.

Compliance with industry standards

Following industry regulations often requires specific tools to perform diagnostics and repairs correctly, ensuring compliance and quality service.

Diesel Mechanic Tools List

Below is a list of recommended tools for diesel mechanics so you have an idea of what various heavy equipment machinery and diesel engine manufacturers might be looking for.

You'll want a cart or rolling toolbox that efficiently separates your tools so they're easy to locate and use.

Adapters

• ¼-inch to ⅜-inch
• ¼-inch to ½-inch
• ⅜-inch to ¼-inch
• ⅜-inch to ½-inch
• ½-inch to ⅜-inch
• ½-inch to ¼-inch
• ½-inch to ¾-inch
• ¾-inch to ½-inch

Allen drivers

• Standard 3/32-inch to ⅜-inch and metric 3-millimeter to 17-millimeter
• Standard Allen wrench set ½-inch to ⅜-inch
• Metric Allen wrench set 2-millimeter to 12-millimeter

¼-inch drive socket set

• Standard (shallow and deep, SAE) 3/16-inch to ⅝-inch
• Metric (shallow and deep) 5-millimeter to 15-millimeter
• Standard depth 3/16-inch to ½-inch
• Deep 3/16-inch to ½-inch
• Standard depth 4-millimeter to 13-millimeter
• Deep 4-millimeter to 13-millimeter
• Short, medium, long extensions
• Ratchet handle
• Universal joint

⅜-inch drive sockets

• Standard (SAE, deep, shallow and impact) 5/16-inch to 1-inch
• Metric (deep, shallow and impact) 7-millimeter to 20-millimeter
• Standard depth 12-point ⅜-inch to ¾-inch
• Deep 6-point ⅜-inch to ¾-inch
• Standard depth 10-millimeter to 19-millimeter
• Deep 10-millimeter to 19-millimeter
• Short, medium, long extensions
• Ratchet handle
• Universal joint
• ⅜-inch to ¾-inch Square drive flexible socket

½-inch drive sockets

• Standard (SAE, deep, shallow and impact) ⅜-inch to 1¼-inch
• Metric (deep, shallow and impact) 10-millimeter to 27-millimeter
• Shallow ½-inch to 1⅛-inch
• Deep ½-inch to 1⅛-inch
• Shallow 13-millimeter to 32-millimeter
• Deep 13-millimeter to 32-millimeter
• Square drive stud remover tool
• Breaker bar
• Short, medium, long extensions
• Ratchet handle
• Universal joint

Extensions

• 2-inch
• 6-inch
• 12-inch
• 24-inch (optional for reaching transmission bellhousing bolts)

Feeler gauge set

• Red handle for exhaust
• Blue handle for intake

Hammers

• Dead blow
• Ball-peen (16 ounce and 24 ounce)
• 4 to 5 lb. sledgehammer
• Plastic 2.5-lb. heavy duty

Impacts (battery- or air-powered) 

• ½-inch
• ⅜-inch
• ¼-inch

Multimeter

• Auto-ranging
• Digital read-out

Pliers

• Standard
• Adjustable
• Needle nose
• Vise-grip set
• Adjustable joint
• Locking
• Side cutters
• Slip-joint
• Snap ring
  • Small reversible
  • Large reversible
  • Flat with 1¾-inch minimum opening
• Brake spring
• Battery nut

Pry bar set

• 1-foot
• 2-foot
• 3-foot

Ratchets

• ½-inch standard ratchet
• ⅜-inch standard ratchet
• ¼-inch standard ratchet
• Breaker bar

Screwdrivers

• Philips (short, medium, long)
• Flatheads
• 1-inch #2
• 6-inch #1
• 6-inch #2
• 1-foot #3
• Blade type: 1-inch, 6-inch, 9-inch, 1-foot, offset

Torque bit drivers

• T10
• T15
• T20
• T25
• T27
• T40
• T45 (medium and long shaft drivers)

Wiring equipment

• Crimping tool
• Wire stripping tool
• Wire cutters
• Handheld torch

Wrenches

• Standard (SAE), 5/16-inch to 1¼-inch
• Metric, 8-millimeter to 22-millimeter
• Combination ⅜-inch to 1¼-inch
• Combination 6-millimeter to 26-millimeter
• Flare nut standard ⅜-inch to ¾-inch
• Flare nut metric 7-millimeter to 19-millimeter
• Adjustable 1-inch to 8-inch
• Adjustable 1-inch to 1-foot
• Torx® wrench set T-15 to T-55
• Pipe wrench 10-inch or 14-inch
• 20-inch reversing chain wrench
• Filter wrench

Files

• 12-inch fine
• 12-inch coarse
• Round
• Half-round
• 6-inch triangle

Punches

• Pin 3/16-inch to ⅜-inch
• Center 5-inch
• Cold chisel
  • ⅜-inch blade to 5-inch length
  • ⅝-inch blade to 6-inch length
  • ⅞-inch blade to 7-inch length
• Starter 3/16-inch to ⅜-inch
• Brass punch

Feeler gauges

• .005-inch to .05-inch
• .005-millimeter to .07-millimeter

Other items for a diesel mechanic tool set

More items you might want to add to a tool list for diesel mechanics include:

• 12-foot measuring tape
• 15-inch aligning bar
• Adjustable all-angle inspection mirror
• Battery post cleaner
• Battery terminal clamp puller
• Cotter key extractor
• Crimp/stripper tool
• Dial caliper
• Drill bits 1/16-inch to ½-inch
• Extractor set (broken bolt)
• Flashlight
• Flexible retrieving and holding tool
• Gasket scraper 1-inch wide
• Hacksaw
• Hearing protection
• Knife
• Magnetic pickup tool (telescoping)
• O-ring pick set
• Rolling head pry bar
• Safety glasses
• Set starter – jumper wires with clips
• Tire air chuck
• Tire gauge (truck-type)
• Valve core replacement tool
• Wire brush
• Work gloves

Common Diesel Mechanic Tool FAQs

What are the essential tools needed for a basic diesel mechanic tool kit?

A basic diesel mechanic tool kit should include fundamental hand tools such as wrenches, socket sets, pliers and screwdrivers. Additionally, including specialty tools like torque wrenches, a multimeter and various adapters will help mechanics effectively tackle diesel engine repairs and maintenance tasks.

Can you recommend any specific brands for high-quality diesel mechanic tools?

.There are many reputable brands known for producing high-quality diesel mechanic tools, and technicians often have their own preferences. It's essential to choose tools that are durable and reliable to withstand the demanding environment of diesel repair work

What are the differences between diesel engine tools and gasoline engine tools?

While there is significant overlap in the tools used for both diesel and gasoline engines, diesel tools are often more robust due to the higher torque and pressure levels found in diesel engines. Additionally, specific tools such as compression gauging tools, diesel injection equipment and more specialized diagnostic tools are unique to diesel mechanics.

How do I properly maintain and store my diesel mechanic tools to ensure their longevity?

To maintain your diesel mechanic tools, clean them regularly after use to remove grease and debris, and store them in a dry, organized toolbox to prevent rust and damage. Periodically checking for wear and tear and ensuring proper lubrication for moving parts will also prolong the life of your tools.

What safety equipment should I have on hand when using diesel mechanic tools?

Essential safety equipment for diesel mechanics includes safety glasses to protect your eyes from flying debris, gloves to safeguard your hands and hearing protection when operating loud machinery. Additionally, having a first-aid kit readily available can help address any injuries promptly.

Are diesel mechanics expected to supply their own tool sets?

Yes, diesel mechanics are typically expected to supply their basic tool sets, especially when starting in the industry. Many employers provide larger, specialized equipment, but mechanics are usually responsible for having essential hand tools. Some employers may offer tool purchase programs or reimbursement options, and students of the automotive, diesel, marine and motorcycle programs at UTI may have access to discounted tool programs to help them build their collection before entering the workforce.¹⁹

Get Started Building Your Diesel Mechanic Tool Set with UTI

Apply for UTI’s Diesel Technology program, which starts frequently during the year at our campus locations nationwide, and use the diesel mechanic tools we provide to train toward pursuing a career!¹ We also have a variety of specialized training programs, like the 12-week Peterbilt Technician Institute (PTI), where eligible students can earn manufacturer-specific certifications that prepare them to pursue employment at one of the 350+ Peterbilt dealerships across North America.^9,15

To learn more and to get in touch with an Admissions Representative, request information online or call 1-800-834-7308 today.