Duramax Repair Shop Valencia CA

 

Book Certified Mechanics for Duramax Diesel Trucks in Santa Clarita

 

Duramax engines deliver power, durability and confidence for towing, hauling and work. But when something feels off, whether it’s power loss, smoke, or warning lights, you need diesel mechanics who understand the system inside and out. RG Brakes & Alignment provides trusted Duramax repair in Valencia CA for drivers and fleet owners across Santa Clarita.

MAKE AN APPOINTMENT

Located at 24309 Creekside Rd #110, our shop has been servicing diesel trucks since 1987. We handle all Duramax platforms, from early LB7 models to today’s 6.6L L5P engines. From diagnostics and emissions service to turbo repair or routine maintenance, our team delivers dependable work with fast turnaround. We also offer full diesel repair in Valencia CA for Cummins, Power Stroke and European diesel platforms.

To schedule service for your Duramax truck, call (661) 259-7098 or use online appointment form.

Duramax Services in Santa Clarita

Car Engine Diagnostics

Duramax Engine Diagnostics

From random misfires to DEF errors or low boost conditions, we run full diagnostic scans using GM/Allison-compatible tools. We identify injector balance issues, sensor faults and fuel delivery problems across all Duramax platforms – LB7, LLY, LBZ, LMM, LML and L5P.
engine

Turbocharger Diagnosis & Replacement

If you hear whistling, experience lag or notice blue/black smoke, your Duramax turbo may be at risk. We test boost pressure, inspect the VGT actuator and unison ring, and replace or rebuild turbos as needed using OEM-quality parts.
DPF and Emissions System Repair

DEF and Emissions System Service

Duramax emissions systems (DPF, DEF injector, SCR, sensors) are prone to failure and clogging. We test and service your system, perform forced regenerations, replace failed sensors or DEF heaters, and help restore drivability and compliance.
Tune Up Services

EGR System Repairs

Excessive carbon buildup in the EGR cooler and valve is a common cause of low performance. Our mechanics clean or replace EGR components to restore smooth acceleration and fuel economy, especially important on LLY and LMM models.
Heating Repair

Glow Plug Circuit Repairs

Duramax glow plug modules and individual plugs are known to fail. We test resistance, replace faulty plugs or controllers and ensure smooth cold starts without warning lights.
Exhaust Repair

Injector Balance Testing & Fuel System Diagnostics

Duramax fuel systems run under high pressure and are sensitive to wear and contamination. We test return rates, check balance rates, replace faulty injectors and inspect CP3/CP4 pumps and fuel pressure regulators for low power or idle issues.
Oil Change

Oil, Fuel & Filter Service

Regular oil and fuel filter changes are key to injector and turbo life. We install ACDelco or OEM-equivalent filters and check for metal, water or sludge contamination.
Cooling System Repair

Cooling System Repairs

From water pump leaks to radiator hose bursts, we inspect and replace failing cooling components to prevent overheating. On older Duramax trucks, we also replace fan clutches, thermostats and coolant reservoirs.
Belt and Hose Replacement

Belt, Pulley & Serpentine Drive Repair

Squealing belts or worn tensioners can lead to accessory failure. We inspect drive components, replace cracked belts and adjust pulleys for reliable alternator and water pump operation.
Preventive Car Maintenance

Electrical Diagnostics

We track down shorts, battery drain issues, alternator faults or damaged glow plug circuits. If you’re experiencing random faults or no-crank conditions, our team can isolate the issue quickly.
Transmission Repair

Allison Transmission Diagnostics

Duramax trucks are often paired with Allison transmissions. We test for slipping, shifting hesitation, line pressure problems and range sensor faults. Fluid changes and reprogramming available.
Tire Installation

Maintenance Packages

We offer complete preventive service for all Duramax engines, including fluid flushes, driveline inspections, tire wear checks and emissions readiness testing.

Common Vehicles With Duramax Engines We Service

We specialize in all Duramax-equipped Chevrolet and GMC trucks and vans, including:

  • Chevy Silverado 2500HD / 3500HD (2001–2025)
  • GMC Sierra 2500HD / 3500HD
  • Chevy Express & GMC Savana vans (6.6L Duramax)
  • Fleet vehicles with Duramax 2.8L or 3.0L inline diesels
  • Duramax diesel-powered commercial and work trucks

No matter if you drive an early LBZ or a new L5P-powered tow rig, we deliver reliable repair solutions to keep your Duramax performing under pressure.

BEST DURAMAX ENGINE REPAIR IN VALENCIA CA

Why Valencia Diesel Truck Owners Choose RG Brakes & Alignment

We’ve been working on Duramax engines since the earliest LB7 trucks hit the streets. Our independent, family-run shop delivers high-level diagnostics and diesel expertise – without the dealership markup.

  • Full Duramax engine diagnostics and repair
  • Emissions, turbo, fuel and DEF systems handled in-house
  • OEM parts and fluids used in every job
  • Transparent, honest estimates
  • Fast turnaround times
  • 2-year warranty on all labor and parts
  • Saturday walk-ins welcome (first come, first served)

ase certified mechanics valencia ca

ABOUT US

#1 Car Repair Shop
in Valencia Since 1987

9119

CARS REPAIRED

24

24 MONTH WARRANTY

2125

HAPPY CUSTOMERS

Book Duramax Repair in Santa Clarita Today

Power loss, warning lights, hard starts or excessive smoke – whatever the issue, we’ll get to the root of it fast. Our diesel techs are trained and equipped to keep your Duramax truck running clean, powerful and reliable.

From high-mileage work trucks to brand-new HD pickups, we offer the attention to detail your diesel deserves.

Call (661) 259-7098 to schedule the service
Visit RG Brakes & Alignment at 24309 Creekside Rd #110, Valencia, CA 91355
Open Mon–Fri 7:30am–5:00pm, Sat 8:00am–3:00pm
Submit online booking requests 24+ hours in advance. Appointments at 8:00 AM on Mondays are not available. Saturday appointments are walk-in only and handled on a first-come, first-served basis.

  • VEHICLE INFORMATION

  • APPOINTMENT DATE & TIME

    NOTE: Please submit your appointments at least 24 hours in advance. Appointments at 8:00 AM on Mondays are not available. Saturday appointments are walk-in only and handled on a first-come, first-served basis.

  • MM slash DD slash YYYY

  • SELECT SERVICE NEEDED

  • CONTACT INFORMATION

Frequently Asked Questions

What are the most common problems with Duramax engines?

Duramax trucks often experience issues with injectors (especially LB7), EGR valve clogging (LLY, LMM), DPF clogging, turbo vane sticking (LBZ, LML) and CP4 fuel pump failures (LML, L5P). Early diagnosis and maintenance help prevent costly repairs.

How often should I change the fuel filter on a Duramax?

Typically every 10,000–15,000 miles, but sooner if the water-in-fuel sensor activates. Keeping fresh filters in place helps protect injectors and the high-pressure pump.

How can I tell if my DPF is clogged?

Loss of power, increased fuel consumption, warning lights or forced limp mode may indicate a clogged DPF. We can test for backpressure and perform a regen or recommend replacement if needed.

Why does my truck blow white smoke when cold?

White smoke at startup may be caused by faulty glow plugs or injectors leaking overnight.

Can I drive my truck if the DEF light is on?

You may be able to drive temporarily, but once the countdown reaches zero, the truck may limit speed.

Do you use GM or Duramax-approved parts?

Yes. We use OEM or ACDelco parts designed for Duramax diesel applications, including approved fluids and emissions components.