Duramax Repair and Service in Cypress, TX
Skeeter's Auto Service repairs Chevy Silverado and GMC Sierra HD Duramax diesels for owners across Cypress and Northwest Houston from our shop at 12133 Old Huffmeister Rd, Cypress, TX 77429. From an LB7 with leaking injectors to an LML with a failed CP4 pump or an L5P with a DEF code, our diesel technicians work on Duramax trucks every day, and the Allison transmission behind them gets the same attention.
We have been fixing trucks on Old Huffmeister since 1992. Every Duramax repair is covered by our 36-month / 36,000-mile nationwide warranty, and every job starts with a diagnosis and a written estimate.
Signs Your Duramax Needs a Shop
- Hard starting, long crank, or a truck that starts and dies
- White smoke and a rough idle when cold, a classic sign of leaking injectors on an LB7
- Loss of power under a trailer, turbo whistle, or a turbo that will not build boost
- Overheating in traffic or under load, common on an LLY
- Oil level rising or fuel in the oil
- Check engine light, or a DEF, DPF, or "exhaust filter" message
- Allison transmission slipping, hunting, or going into limp mode under load
- Sudden loss of power and a no-start on an LML, which can mean a CP4 pump failure
Call 281-469-1152 or book online. If the truck is not safe to drive, 24/7 towing is available to bring it in.
Duramax Generations We Service
- LB7 (2001 to 2004). Typical work: injector replacement with updated parts and injector cup sealing, fuel filter head repair, and cooling system upkeep on high-mileage trucks.
- LLY (2004.5 to 2006). Typical work: overheating under tow, turbo inlet (mouthpiece) restriction, head gaskets on trucks that have been run hot, and cooling system upgrades.
- LBZ (2006 to 2007). The reliable one. Typical work: injector and turbo service, glow plugs, and routine maintenance.
- LMM (2007.5 to 2010). The first Duramax with a DPF. Typical work: DPF and regeneration faults, fuel dilution of the oil, and injector service.
- LML (2011 to 2016). Typical work: CP4 high-pressure fuel pump failure and full fuel system cleanup, DEF heater and quality codes, NOx sensor and EGR faults, and injector service.
- L5P (2017 to present). Typical work: DEF and emissions codes, turbo and actuator faults, and maintenance done with the diagnostic equipment a newer truck needs.
The model year and the RPO code on the glove box sticker tell us which engine you have and where to start.
How We Diagnose a Duramax
- Full scan of the engine, Allison transmission, and emissions modules with diesel-capable equipment
- Live data review: rail pressure, injector balance rates, boost and VGT position, EGT, and regeneration history
- Fuel system tests: lift pump and high-pressure pump output, fuel filter condition, water separation, and, on LML trucks, a check for metal in the fuel system before any pump work
- Injector return flow (balance rate) testing on LB7 and later trucks
- Cooling system pressure test and fan clutch check for overheating complaints
- Glow plug and starting circuit tests
- Emissions system review: DPF soot load, DEF quality and dosing, and sensor health
You get the findings and a written estimate before any repair starts. Our diagnostics page covers how we handle warning lights across the shop.
Duramax Repairs and Services We Perform
- Injector testing, replacement, and injector cup sealing
- CP3 and CP4 high-pressure fuel pump replacement, including CP4 fuel system cleanup on LML trucks
- Lift pump installation and fuel filter head repair
- Turbocharger repair, VGT actuator service, and turbo inlet repair
- EGR valve and EGR cooler service
- DPF, DEF, and emissions system diagnosis and repair
- Glow plug replacement
- Head gasket and cooling system repair, including fan clutch, radiator, water pump, and thermostat
- Oil and fuel filter service with the correct diesel-rated oil
- Allison transmission fluid and filter service, transfer case and differential service
- Complete Duramax engine replacement or rebuild
Duramax Maintenance That Prevents the Big Repairs
- Fuel filter and water separator service on schedule; the Duramax common-rail system is precise and unforgiving of water and dirt
- Oil and filter changes with the correct diesel-rated oil, and oil level monitoring on LMM trucks
- Coolant condition testing and cooling system service before summer, especially on an LLY that tows
- Allison transmission fluid service on trucks that tow, before the fluid is burned
- Emissions system health checks so a DPF or DEF problem is caught before a limp-mode drive home
Performance, Towing, and Fleet
A Duramax that tows a fifth wheel or works every day can benefit from turbocharger and exhaust upgrades, injector upgrades, and ECU tuning set to the load you actually pull, and we will tell you plainly when a modification is not worth it for the way you drive. For work trucks and fleets we offer diesel service capacity up to F-550-class trucks, priority scheduling, secure after-hours key drop and pick-up, per-unit service records, and a fleet charge account through CB Charge.
Diesel Service Beyond the Engine
A Duramax truck is a whole vehicle, and the parts around the engine wear faster on a truck that tows. On the same visit we handle brakes sized for towing, alignment for lifted and loaded trucks, AC for Cypress summers, transmission and transfer case fluid service, and steering and suspension wear from the extra weight up front. Our diesel repair page covers everything we do for diesel trucks, and fleet accounts can put every unit on one schedule.
Why Cypress Drivers Choose Skeeter's
- Family owned since 1992. Skeeter bought the shop on Old Huffmeister in 1992 and his family runs it today. Read our story.
- 36-month / 36,000-mile nationwide warranty on our repairs.
- ASE-certified technicians working on all makes and models, domestic, European, and Asian, gas and diesel.
- Digital inspection with photos and video sent to your phone, so you see what we see before approving any work.
- Courtesy shuttle during business hours, ride share, 24/7 towing, and secure after-hours key drop and pick-up, so the visit fits around your day.
- Exterior car wash with every service.
- Financing available through Synchrony Car Care and American First Finance.
- Straight answers. You get the findings and a written estimate before any work starts, and we tell you what can wait.
Current offers, including our discount for Cy-Fair ISD teachers and staff, are on the specials page. See what your neighbors say on our reviews page.
Serving Cypress and Northwest Houston
Skeeter's Auto Service is at 12133 Old Huffmeister Rd in Cypress, TX 77429, a few minutes north of US-290 off Huffmeister Rd. Drivers come to us for Duramax repair from across Cypress, including Coles Crossing, Ravensway, and Tower Oaks, as well as Bridgeland, Fairfield, Towne Lake, Copperfield, Jersey Village, and the 77433 side of town. If you have been searching for a Duramax mechanic near me from anywhere along the 290 corridor, Tomball, or Spring, we are a short drive.
Duramax Repair FAQs
Do you work on the older LB7 and LLY trucks?
Yes, every generation from the LB7 through the current L5P. LB7 injector jobs and LLY cooling work are regular jobs in our bays.
My LB7 smokes white when cold and the oil level is rising. What is that?
Almost always leaking injectors. We confirm with balance rate testing, then replace them with updated injectors and reseal the injector cups so the repair lasts.
What is the CP4 problem on the LML?
The 2011 to 2016 LML uses a CP4 high-pressure fuel pump that can fail and send metal through the fuel system. A sudden loss of power and a no-start is the classic sign. We check the fuel system for contamination first, because a pump replacement without a cleanup will fail again.
My truck says "exhaust filter" or keeps regenerating. Can you fix that?
Yes. We diagnose and repair DPF, DEF, and EGR faults in-house, including forced regenerations, DEF heater and quality problems, and sensor replacement.
Do you service the Allison transmission?
Yes. Fluid and filter service, and diagnosis of slipping, hunting, or limp mode, which on a truck that tows is often fluid condition before it is a hard part.
How often should the fuel filter be changed on a Duramax?
Most trucks are due every 10,000 to 15,000 miles, and sooner if you tow or fuel at a lot of different stations.
Is the repair covered by a warranty?
Yes. Repairs at Skeeter's Auto Service carry a 36-month / 36,000-mile nationwide warranty.
Is there a Duramax repair shop near me in Cypress that handles fleet trucks?
Yes. Priority scheduling, per-unit records, after-hours drop-off and pick-up, and a fleet charge account for businesses running Duramax-powered trucks.
Schedule Duramax Repair in Cypress, TX
Call 281-469-1152 or book an appointment online. We are open Monday through Friday, 7:00am to 5:00pm, with secure after-hours drop-off and pick-up, a courtesy shuttle during business hours, and an exterior car wash with every service. Family owned since 1992, and every repair is backed by our 36-month / 36,000-mile nationwide warranty.