Dedicated diesel mechanic
Diesel engines are not gas engines with bigger numbers. They run higher pressures, tighter tolerances, and demand specific tools and training. We have a diesel-focused mechanic on the floor every day.
Boulder Diesel by Legacy
Diesel Truck Repair in Boulder
Light-duty diesel pickup repair, fleet diesel service, and the work-truck expertise Boulder and the Front Range count on. Power Stroke, Cummins, Duramax, all in-house.
The diesel pickups that move Boulder and the Front Range deserve a shop that understands them. Boulder Diesel is now part of Legacy Automotive, with a dedicated diesel mechanic, the right tools, and the experience to do the work right the first time.
Diesel takes a specialist.
A diesel pickup is not a gas truck with bigger numbers. The fueling, the air management, and the emissions systems all reward a shop that knows the platforms.
Light-duty diesel pickups
Power Stroke (6.0, 6.4, 6.7), Cummins (5.9, 6.7), and Duramax (LB7, LLY, LBZ, LMM, LML, L5P). The trucks Boulder and Erie work crews drive every day.
Diesel fleet experience
We service the diesel pickups that move the oil and gas industry, the construction crews, and the contractors that connect Boulder to the Front Range. Priority scheduling for fleet accounts.
Boulder Diesel under Legacy
What used to be Boulder Diesel is now part of Legacy Automotive. Same diesel expertise, broader resources, single point of contact. The diesel work runs through our shop, with our warranty and our team.
Diesel work we do every week.
These are the services diesel owners and fleet managers bring to us most often. Each one is a job our diesel mechanic has done many, many times.
Injector and high-pressure fuel system service
Injector replacement, high-pressure pump diagnosis, fuel rail and return line service. Common on 6.0 and 6.4 Power Strokes, 6.7 Cummins, and aging Duramax LB7 and LLY trucks.
Turbocharger service and replacement
Turbo diagnosis, VGT actuator service, oil supply and return lines, and full turbo replacement when required. We do not condemn turbos without the data to back it up.
EGR, DPF, and emissions diagnosis
EGR cooler and valve service, DPF diagnosis and forced regen, DEF system troubleshooting. We work within current emissions regulations and tell you straight what is and is not legal.
Glow plug and cold-start diagnosis
Glow plug testing and replacement, glow plug module service, and cold-start diagnosis for Colorado winters that drop below zero overnight.
Coolant system, head gaskets, EGR cooler
6.0 Power Stroke head gasket and stud upgrade, EGR cooler replacement, oil cooler service. We know the platform's failure points and how to fix them once.
Transmission and transfer case service
Allison, 4R100, 5R110, 5R110W, 6R140, 68RFE, AS69RC fluid service and diagnosis. Transfer case fluid and chain service for working trucks that earn their miles.
Brake, suspension, and steering on heavy-duty trucks
1500/2500/3500 series brake, suspension, and steering work. Loaded trucks behave differently and we set them up to handle the loads they actually carry.
Every major light-duty diesel.
From the 5.9 Cummins to the L5P Duramax to the 6.7 Power Stroke. The diesel pickups Boulder and the Front Range run every day.
- Ford Power Stroke 6.0L
- Ford Power Stroke 6.4L
- Ford Power Stroke 6.7L
- Ram Cummins 5.9L
- Ram Cummins 6.7L
- Chevy/GMC Duramax LB7
- Chevy/GMC Duramax LLY/LBZ
- Chevy/GMC Duramax LMM
- Chevy/GMC Duramax LML
- Chevy/GMC Duramax L5P
Working Trucks, Working Shop
The trucks that work the Front Range.
Diesel pickups in the Boulder and Erie corridor work for a living. Oil and gas crews driving from Weld County, contractors hauling materials to the foothills, ranchers and landscapers, small construction outfits, and the personal trucks that pull trailers to the mountains every weekend. None of those trucks can afford to sit.
We treat downtime as the enemy. Priority scheduling for fleet accounts and working trucks. Diagnosis before parts. Photo documentation that travels with the truck. Three-year, nationwide NAPA warranty so the truck is covered no matter where the next job takes it.
What diesel drivers say.
“Run a small contracting outfit out of Erie. Three F-250 Power Strokes and a Ram Cummins. Legacy keeps them all running, prioritizes us when one goes down, and the photo invoices make my bookkeeper's life easier.”
Garrett W.
Ford F-250 Power Stroke
“Had injector issues on my LBZ Duramax for over a year. Two other shops shotgunned parts at it. Legacy did real diagnosis, found the actual failed injector, and the truck has run perfect since.”
Drew P.
2007 GMC Sierra 2500 Duramax
“6.0 head gaskets and studs on my Excursion. They did the job right, with photos through the whole process, and warrantied it for three years. Could not ask for more.”
Maria L.
2005 Ford Excursion 6.0L
“Run a small contracting outfit out of Erie. Three F-250 Power Strokes and a Ram Cummins. Legacy keeps them all running, prioritizes us when one goes down, and the photo invoices make my bookkeeper's life easier.”
Garrett W.
Ford F-250 Power Stroke
“Had injector issues on my LBZ Duramax for over a year. Two other shops shotgunned parts at it. Legacy did real diagnosis, found the actual failed injector, and the truck has run perfect since.”
Drew P.
2007 GMC Sierra 2500 Duramax
“6.0 head gaskets and studs on my Excursion. They did the job right, with photos through the whole process, and warrantied it for three years. Could not ask for more.”
Maria L.
2005 Ford Excursion 6.0L
Diesel questions, answered.
Yes. Our focus is light and medium-duty diesel pickups: 1500/2500/3500 Ram, F-250 and F-350 Super Duty, and 2500/3500 Silverado and Sierra. The diesel platforms most common on Boulder-area work crews and Front Range fleets.
Ready to Book?
Schedule your diesel service.
Free loaner vehicles for qualifying repairs. Photo and video documentation on every job. Three-year, 36,000-mile NAPA warranty. Priority scheduling for fleet accounts.