The Lemon Index
The 6.6 L V8 turbo diesel in the Chevrolet Silverado 2500HD/3500HD and GMC Sierra 2500HD/3500HD, model years 2006–2007. Owners filed 186 complaints about trucks with it (matched by VIN); 8% name the engine, #8 of the 12 diesel truck engine generations we track (1 = the most).
Known issues, checked against owner complaints
None of the issues people usually talk about stands out in this engine's complaints to NHTSA.
Also often talked about, but not standing out in complaints to NHTSA: injectors (1 of 186, 0.5%, peers 2.5%). That doesn't mean it never happens, only that owners rarely file it with the government.
What YouTube owners say Tone 0-100, higher = more praise than trouble.
Average owner tone 44/100 across 2 model years, from 151 videos about this engine and its cars.
Most-watched videos
- A truck to keep very nice. My 4th LBZ Duramax 1,413,387 views
- LBZ Duramax Truck - Grandpa to Golly! NEW Low Mile Shop Truck Upgrades! 1,402,522 views
- LBZ DURAMAX VS CAN-AM X3 | What’s faster? 702,757 views
Counted from video titles and captions: praise words against trouble words, weighted by views. Videos only count when the title names this engine or a car that had only this engine in those years.
Owner complaints by model year
Counts of complaints filed so far. Older trucks have had longer to collect them, and popular years draw more because more were sold: no one reports sales by engine, so there's no per-truck rate. Compare the shares below instead.
What owners complain about
Share of this engine's complaints that name each area (one complaint can name several).
What owners write
| Complaints that | Count | Share | Median, other diesel truck engines |
|---|---|---|---|
| Say the engine stalled, shut off or lost power | 13 | 7.0% | 7.8% |
| Mention the turbo | 6 | 3.2% | 1.0% |
| Mention coolant loss or overheating | 5 | 2.7% | 0.8% |
Counted from the owner's own words in each complaint (all of the truck, not only the engine). A share, not a failure rate.
When problems show up
Half of the owners who gave a mileage reported the problem between 27,606 and 89,000 miles; the middle report was at 51,000 miles (174 complaints with a mileage).
Recalls that name this engine 0
No NHTSA recall on these trucks names this engine.
NHTSA recalls on these trucks and years whose text names this engine (its size, or diesel / Cummins / Duramax / Power Stroke). The rest (brakes, air bags, wiring ...) are on each truck year's page.
Trucks with this engine
In owners' words
Air bag front impact sensor are no longer available from manufacturer. Airbag system in inoperable.
2007 Chevrolet Silverado 2500HD/3500HD and GMC Sierra 2500HD/3500HD owner · NHTSA complaint 11718107
Front air bag sensor part is not available. Part number 85597996 has been discontinued without a replacement. As such, I have no airbag system on my truck.
2007 Chevrolet Silverado 2500HD/3500HD and GMC Sierra 2500HD/3500HD owner · NHTSA complaint 11695425
Odometer Fraud. The contact considered purchasing a 2007 GMC Sierra 2500 from a local dealer. The contact stated that vehicle mileage was listed as 159,000, but the Carfax report listed the mileage as 400,000.
2007 Chevrolet Silverado 2500HD/3500HD and GMC Sierra 2500HD/3500HD owner · NHTSA complaint 11679014
Against the other diesel truck engine generations
| Engine | Years | Complaints | Name the engine | Name the fuel system | Stalled or lost power | Recalls naming it |
|---|---|---|---|---|---|---|
| 6.0 Power Stroke | 2003–07 | 1,708 | 34% | 16% | 31% | 2 |
| 6.4 Power Stroke | 2008–10 | 572 | 28% | 7% | 11% | 2 |
| Duramax L5P | 2017–26 | 1,229 | 16% | 10% | 14% | 2 |
| 7.3 Power Stroke | 1999–03 | 2,049 | 15% | 5% | 12% | 1 |
| Duramax LML | 2011–16 | 779 | 13% | 20% | 17% | 0 |
| 6.7 Cummins | 2007–26 | 7,667 | 11% | 8% | 6.4% | 9 |
| 6.7 Power Stroke | 2011–26 | 5,640 | 10% | 11% | 7.8% | 6 |
| Duramax LBZ | 2006–07 | 186 | 8% | 5% | 7.0% | 0 |
| Duramax LMM | 2007–10 | 385 | 8% | 6% | 5.2% | 0 |
| Duramax LB7 | 2001–04 | 592 | 7% | 17% | 5.4% | 1 |
| Duramax LLY | 2004–06 | 374 | 7% | 11% | 7.8% | 0 |
| 5.9 Cummins | 1999–07 | 3,245 | 4% | 7% | 5.0% | 0 |
Shares of each engine's own complaints, matched by VIN. They show what owners complain about, not how often trucks break. Every diesel truck engine compared
Quick answers
Is the Duramax LBZ reliable?
No one reports sales by engine, so there's no per-truck score. Of the 186 complaints owners filed about trucks with it, 8% name the engine, #8 of 12 diesel truck engine generations we track (1 = the most).
What trucks have the Duramax LBZ?
In our data: the Chevrolet Silverado 2500HD/3500HD and GMC Sierra 2500HD/3500HD, model years 2006–2007, matched by the VIN in each owner complaint.
What are the most common Duramax LBZ problems?
In owner complaints to the government: brakes, transmission & drivetrain, steering.
How many recalls name the Duramax LBZ?
0 NHTSA recalls on these trucks name it.
Source: NHTSA owner complaints (FLAT_CMPL + COMPLAINTS_RECEIVED_2025-2026), received through 20261109; engines: NHTSA vPIC VIN decoder; NHTSA recalls API. Engine names and years: GM (RPO codes).