GT3788VA Turbocharger for GMC Chevy Duramax LLY LBZ LMM 6.6L
The GT3788VA is a Garrett VGT turbocharger for the 2004-2010 GMC Sierra and Chevrolet Silverado 2500HD/3500 with the Duramax LLY, LBZ, and LMM 6.6L diesel V8. These three Duramax generations (2004.5-2010) all use variations of the Garrett GT3788VA VGT turbo, replacing the IHI RHG6 from the LB7. Garrett part 848212-0001/736554-5015, GM OEM varies by generation. Built new, dynamically balanced, ships with gaskets. We supply diesel shops and distributors.
Turbo Model
GT3788VA (Garrett VGT)
OEM / Interchange Numbers
848212-0001, 848212-5001, 736554-0015, 736554-5015, 736554-5015S, 759622-0005
Application
2004.5-2010 GMC Sierra / Chevrolet Silverado 2500HD/3500 Duramax LLY/LBZ/LMM 6.6L
Service & Support
- 1-Year Warranty
- US Stock, Fast Dispatch
- Bulk Orders Welcome
- White-Label Support
- Fully Certified
Your Source for Quality Diesel Engine Parts
FAQ
The GT3788VA fits the 2004.5-2010 GMC Sierra and Chevrolet Silverado 2500HD/3500 with the Duramax LLY, LBZ, or LMM 6.6L.
No. The 2001-2004 LB7 uses the IHI RHG6. The GT3788VA is for LLY/LBZ/LMM only.
Yes. The GT3788VA covers all three generations (LLY 2004.5-2005, LBZ 2006-2007, LMM 2007.5-2010) with different Garrett sub-part numbers.
Brand new, dynamically balanced. No core charge. One-year warranty.
Yes. US stock, volume pricing for diesel shops and distributors.
GT3788VA for Duramax LLY/LBZ/LMM: Three Generations, One Turbo Family
When GM switched from the IHI RHG6 on the LB7 to the Garrett GT3788VA starting with the LLY in 2004.5, they standardized on Garrett for three consecutive Duramax generations. The LLY (2004.5-2005), LBZ (2006-2007), and LMM (2007.5-2010) all use GT3788VA variants.
Duramax turbo timeline
| Years | Duramax | Turbo |
|---|---|---|
| 2001-2004 | LB7 | RHG6 (IHI) |
| 2004.5-2010 (this page) | LLY/LBZ/LMM | GT3788VA (Garrett) |
Common failure modes
- VGT vane sticking — the most common issue across all three generations. Soot from EGR fouls the vane mechanism.
- Unison ring wear — the ring that controls vane position wears over time.
- Bearing wear — shaft play at 150k-250k miles on trucks that tow regularly.
Installation
- Direct bolt-on. Ships with gaskets.
- Flush oil feed line. Prime before startup.
- Verify VGT operation via scan tool.
See our quality process for details.
