Diamond Diesel and Truck Repair

Certified Diesel Engine
and Truck Repair

Diesel & Semi-Truck Service and Repair

Diamond Diesel and Truck Repair provides dependable repair and maintenance for diesel engines and heavy-duty vehicles in Franklin, Lincoln, Warren, Callaway, Montgomery and St. Charles counties. We work on everything from semi-trucks and tractors to large agricultural and construction equipment. Our services include both in-shop repairs and mobile assistance, with 24/7 roadside support available when you need it most. Backed by skilled diesel technicians, we take pride in delivering straightforward, trustworthy service to keep your trucks and equipment operating at peak performance so you can stay on schedule.

Engine Services

Expert diagnostics and repairs to keep your engine and transmission running strong.

Maintenance

Preventative care and driveline repairs to extend the life of your truck.

Auto Repair

Preventative care and driveline repairs to extend the life of your truck.

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Certified Diesel & Heavy Equipment Experts

At Diamond Diesel and Truck Repair, our team’s certifications reflect our dedication to delivering top-quality service for diesel engines and heavy equipment. Our credentials include:

ASE Heavy-Duty Maintenance
Caterpillar Heavy Equipment
CAT, Cummins, PACCAR, Detroit, and MaxxForce Engines
Hydraulic Systems
Fuel System Diagnostics
Eaton & Mack Transmission Repair
CNG & LNG Systems
DOT Inspections

We combine proven expertise with hands-on experience to handle even the toughest repair challenges.

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In-Shop & 24/7 Roadside Service

From routine maintenance to emergency repairs, Diamond Diesel and Truck Repair has you covered—whether you’re in our fully equipped shop or stuck on the side of the road. Our around-the-clock roadside service means you’re never alone when trouble strikes.

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Engine Repair – Skilled technicians restoring power and performance.
Maintenance Services – Brakes, tires, oil changes, and more to keep you rolling.
Transmission Repair – Smooth, reliable shifting you can depend on.
Driveline Repair – Expert care for the parts that keep your wheels turning.
Diagnostics – Advanced technology to pinpoint and fix problems fast.
Custom Lighting & Accessories – Personalize and improve your equipment.
24/7 Roadside Repairs – Rapid response to get you back on schedule.

What People are Saying

    
 
 
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   Ahmed  
 
 
 
 Trustindex verifies that the original source of the review is Google. They did great work had a radiator fail and within a couple hours they had me back on the road. Will definitely use them again
  
 
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   AZFT  
 
 
 
 Trustindex verifies that the original source of the review is Google. High quality service
  
 
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   Alex  
 
 
 
 Trustindex verifies that the original source of the review is Google. Sure! Here's your updated review with the mention of their politeness: --- ⭐️⭐️⭐️⭐️⭐️ I had a great experience with this roadside truck repair shop! They were **fast**, **cheap**, and extremely **helpful**. My truck broke down unexpectedly, and within minutes of calling, a technician was on-site and ready to help. They diagnosed the issue quickly and were very **polite** throughout the entire process. It's rare to find service that's both efficient and friendly. Highly recommend!
  
 
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   Luis  
 
 
 
 Trustindex verifies that the original source of the review is Google. Really great people to work with got my truck up n running! Appreciate y’all’s help
  
 
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   Ethan  
 
 
 
 Trustindex verifies that the original source of the review is Google. Great shop had the work done quickly and correctly while they were also good on the price.
  
 
      Posted on Google  
   
   No  
 
 
 
 Trustindex verifies that the original source of the review is Google. Evan and Harley are spectacular! I was down on my luck 10 hours into my drive when I blew a tire and was stranded with no where to go. It was midnight and no where else was open or answering,  One quick search and I found these guys! They went above and beyond to ensure I was back on the road in no time. I would %1000 recommend this business, they really care for their customers

Your Partner in Keeping Trucks on the Road

At Diamond Diesel, we know downtime costs you money. That’s why we work fast, use quality parts, and stand behind every repair we make. From big rigs to farm equipment, our goal is simple—get you back to work and keep you there. We treat every truck like it’s our own, because when your wheels turn, your business moves forward.

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Diamond Diesel - Keeping Tucks on the Road

Why Drivers Trust Diamond Diesel

Our customers keep coming back for one reason—results. We combine expert skill, honest communication, and fair pricing to deliver repairs you can rely on. No hidden fees. No cutting corners. Just dependable service from certified diesel mechanics who care about your success. When you need a repair team that’s as committed to your truck as you are, Diamond Diesel is the clear choice.

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Ready to Get Back on the Road?

Don’t let repairs slow you down. Whether it’s routine maintenance, emergency roadside service, or major repairs, Diamond Diesel and Truck Repair is here to keep your trucks and equipment running strong. Call us today and experience the service trusted by drivers and fleets on I-70 and I-44.

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Certified Diesel Engine and Truck Repair