Diesel Mechanic Services in Phoenix, AZ

Available Any Time Day Or Night

The diesel mechanics at Onsite Truck & Equipment Repair are experts in truck and trailer repair in Phoenix, Arizona. We work on heavy-duty diesel trucks, medium and light-duty trucks, fleet vehicles, RVs, and all types of equipment, including forklifts. Plus, we’re more than just a truck repair shop—we offer mobile service, emergency roadside assistance services, and afterhours service to accommodate your schedule and your needs. With all our services, we’ll maintain your manufacturer’s warranty, and you’ll get NAPA’s nationwide warranty. So, don’t hesitate to give us a call, 24 hours a day, seven days a week, 365 days a year.

Our Diesel Mechanic Services

  • 24-hour Emergency Road Service
  • Aerial Devices
  • Afterhours Maintenance
  • Air Brake System Repair
  • Air Filter Replacement
  • Annual Inspections
  • Brake Repair & Service
  • Check Engine Light
  • Clutch Repair & Replacement
  • Coolant / Antifreeze Flush
  • Cooler Repair
  • Diesel Repair
  • Differential Repair
  • Differential Repair & Replacement
  • DOT Inspections
  • Drivability Issues
  • Driveline Repairs
  • Electrical Repair
  • Emission System Repairs
  • Engine Repair & Replacement
  • Exhaust / Muffler Repair & Service
  • Fabrication
  • Fleet Maintenance
  • Heating Systems
  • Heavy-Duty Truck Repair
  • Hydraulic Repairs
  • Lift Gate Service
  • Light & Medium-Duty Truck Repair
  • Mobile Service
  • Preventive Maintenance
  • Radiator Repair & Service
  • Refrigerated Transport
  • Road Side Assistance
  • Scheduled Maintenance
  • Steering
  • Suspension
  • Transmission Repair
  • Truck & Equipment Lights
  • Truck A/C Repair
  • Truck Diagnostics
  • Truck Oil Change / Lube Service
  • Tune-ups
  • Welding
  • Wheel / Tire Alignment

Contact Onsite Truck & Equipment Repair Today!

Contact Us

Our Medium & Heavy-Duty Truck Repair Services

Our team of certified diesel mechanics have the experience and the expertise to handle basic to complex commercial truck repair and maintenance, both in-shop and onsite. From DOT inspections and preventive maintenance, to comprehensive diesel engine repairs, trust the technicians at Onsite Truck & Equipment Repair, Phoenix's top-rated choice for fleet owners and owner-operators.

A/C System Repair

Your comfort in the cabin is the key to working your best. Our technicians make sure your cooling and ventilation are in top shape so that you can stay on the road whatever the weather.

See more about A/C System Repair>


Vehicle pulling to the left or right? Uneven or rapid tire wear? Is your steering wheel crooked when driving straight? You probably need a wheel alignment.

See more about Alignment>

DOT Inspections & Mobile Preventive Maintenance

The safety and reliability of your vehicle is our top priority. Our licensed technicians will keep you compliant with Arizona’s DOT, driving safely, and get you back to work quickly.

See more about DOT Inspections & Mobile Preventive Maintenance>

Diagnostics & Electrical Repair

We have a systematic approach to diagnostics that gets us to the root of a problem quickly. Whether we're dealing with complex issues or something simple, we have a set of procedures we follow to ensure we’re always improving.

See more about Diagnostics & Electrical Repair>

Driveline Repair

From general driveline service to catastrophic failure repairs, our Heavy Equipment Technician (HET) and Red Seals certified diesel mechanics are driveline experts.

See more about Driveline Repair>

Engine Repair, Overhaul & Rebuild

Every day that your truck is in the shop is a day that you aren’t on the road, making money. Onsite Truck & Equipment Repair knows and understands the importance of getting repairs done quickly, correctly and affordably. No job is too big or too small for our experienced team.

See more about Engine Repair, Overhaul & Rebuild>

Exhaust & Aftertreatment

Exhaust issues can lead to decrease in power, acceleration, and fuel economy. They'll often sound bad but their outcomes can be even worse. Be sure to have your exhaust serviced regularly to avoid potential problems.

See more about Exhaust & Aftertreatment>


No job is too big or too small for our experienced team. We can take care of everything from a simple body repairs to more complex problems such as issues with the brakes, fuel injection system, clutch, or transmission.

See more about Maintenance>

Suspension Repair

Regular wear and tear on your suspension makes it hard to get where you need to go and puts the integrity of your vehicle at risk. We get you aligned and back on the road with little downtime.

See more about Suspension Repair>

Transmission & Clutch Repair

While clutch designs vary depending on light, medium, or heavy-duty applications, they all break down and get worn eventually. Getting them serviced regularly keeps you safe and secure on the road.

See more about Transmission & Clutch Repair>

Our Light-Duty Pickup Truck Repair Services

Select a service from the list below to see more information:

A/C Repair

Recharge, repair, and get your A/C pumping back at full capacity.

See more about A/C Repair Services>

Brake Repair

Not as sexy as a turbo but just as important. Callipers, pads, full service.

See more about Brake Repair Services>

Coolant System Repair

Proper maintenance saves money. Ensure your coolant is running right.

See more about Coolant System Repair Services>

Diesel Diagnostics

Our mechanics use the best tools on the market to ensure accurate readings.

See more about Diesel Diagnostics Services>

EGR & DPF Aftertreatment Cleaning

Downtime can be costly — we get it. Our services fix problems, permanently.

See more about EGR & DPF Aftertreatment Cleaning Services>

Electrical Repair

Ground wires, batteries, ECMs: well figure out your electrical issues.

See more about Electrical Repair Services>

Engine Repair & Rebuild

Rebuild, repair, or replace? We'll help you find the right answer for your truck.

See more about Engine Repair & Rebuild Services>

Fuel System Repair

A properly maintained fuel system is essential to top performance.

See more about Fuel System Repair Services>

General Maintenance

Pay small bills now and save on the big bills later. Full inspection service available.

See more about General Maintenance Services>

Oil & Fluid

Keeping your fluids maintained is essential to the proper function and longevity of your vehicle.

See more about Oil & Fluid Services>

Suspension Repair

Custom suspension installs and suspension repair is one of our specialties.

See more about Suspension Repair Services>

Transmission Repair

A small amount of maintenance work now can pay off huge in the future.

See more about Transmission Repair Services>

A Phoenix Truck Repair Shop That Cares

In the beginning, Henry and Sheree had only one service rep. Today the business has grown to two shops with nine service reps. The goal at Onsite Truck & Equipment Repair is to make the customer’s job easier and less stressful, and it has been since day one. We genuinely care and push to have the best talent in the truck repair industry.Now with 20 years of truck repair experience, Henry is proud to be living the American dream, running a family business and providing a valuable service to other businessowners and operators like himself. He loves working with people, solving problems, and building lasting relationships with his customers. Hard work, dedication, and honesty have taken him a long way. He stands by those principles and looks forward to passing them on to his and Sheree’s four children.

NAPA Auto Parts Logo

Vehicles We Service & Repair