The 6.6L Duramax LBZ (2006-2007 only) is widely considered the best Duramax ever. No DPF, no DEF, 360 HP / 650 lb-ft, and the Allison 1000 transmission. Two-year production run makes them sought after - and surprisingly clean LBZ trucks command premium prices.
No DPF, no DEF, plenty of power, durable Allison. LBZ trucks are the most desirable Duramax for collectors and serious users. Just don't tune them too hard or you'll crack pistons.
LBZ pistons crack between the ring lands when tuned above 600 HP. Stock LBZ trucks are bulletproof - high-HP tunes destroy pistons. Forged pistons fix it.
Get a free diagnosis →The factory water pump fails by 150,000 miles. Coolant leak from the weep hole is the warning sign. Replacement is $400-$700.
Get a free diagnosis →The 1000-series Allison is incredibly tough but tunes over 500 HP overwhelm the stock TCM. Aftermarket TCM tunes and clutch upgrades extend life.
Get a free diagnosis →The fuel filter housing develops cracks and the integrated heater fails. Updated GM filter heads or aftermarket FASS solves both.
Get a free diagnosis →LBZ EGR coolers fail at much lower rates than LLY trucks. Still possible - watch for coolant loss without external leak.
Get a free diagnosis →Standard cold-start glow plug issues. Easy fix.
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GM TSB 06-06-04-038 covers turbo VGT cleaning. TSB 07-06-04-026 covers fuel filter head replacement. No major open recalls. Allison TSB AT3220 covers TCM software updates for 1000-series transmissions. LBZ trucks are pre-emissions (no DPF/DEF) which simplifies long-term ownership significantly.
If you see a check engine light, these codes most often relate to the issues above. Click any code for full diagnosis steps.
No DPF, no DEF, 360 HP / 650 lb-ft, stout Allison transmission. Two-year production run means limited supply, driving up resale.
Mild tunes are fine. Above 500 HP you risk cracking pistons - upgrade to forged pistons before going big.
400,000+ miles stock with proper maintenance. The block, heads, and rotating assembly are nearly bulletproof.
Clean low-mileage LBZ trucks command $25,000-$45,000 - far above similar-year gas trucks. Premium reflects desirability.
For purists yes - no DPF. LMM (2007.5-2010) is similar but adds emissions hardware. Both share the same long block.
EFILive tune + 4" downpipe-back exhaust + intake. Gains 100+ HP without risking the rotating assembly.