Duramax

[Nickw059]

I'm looking into getting a duramax. Which engine is the best one? and Why? whats the diffrence between LBZ and LLY ?

[mrmanners]

Opinions very widely on this. The LB7 are strong, offer good fuel economy but are prone to injector problems. 04-05 LLYs are have issues with overheating but an inexpensive DIY can fix that quite easily, the 06-07 Classic with the LBZ and LLY are both good the LBZ is tuned down some though compared to the LLY and the fuel econ is not quite as good. The LMMs are great, all the bugs worked out with the exception of the added EPA exhaust ad ons like DPF.

I have an 06 LLY. Bought it in Apr. Love every minute of it so far.

Take care,

[dwill3015]

Opinions very widely on this. The LB7 are strong, offer good fuel economy but are prone to injector problems. 04-05 LLYs are have issues with overheating but an inexpensive DIY can fix that quite easily, the 06-07 Classic with the LBZ and LLY are both good the LBZ is tuned down some though compared to the LLY and the fuel econ is not quite as good. The LMMs are great, all the bugs worked out with the exception of the added EPA exhaust ad ons like DPF.

I have an 06 LLY. Bought it in Apr. Love every minute of it so far.

Take care,

It's actually the opposite. The LLY in the early 06's is virtually the same as the LBZ, but the LBZ has a hotter tune and has more HP and torque.

This is from wikipedia:

The 2006 LLY (engine code "2") debuted in the beginning of 2006 and ended production with the start of the 2007 calendar year. Mechanically it is identical to the LBZ and is mated to the new 6 speed Allison transmission however it retained the LLY designation.

The LBZ (engine code "D") debuted in the earlier part of 2006 and continued into 2007 sold only in the "classic" body style. It has a more powerful tune loaded into the computer that allows it produce more power and torque.

Changes include:

Cylinder block casting and machining changes strengthen the bottom of the cylinder bores to support increased power and torque
Upgraded main bearing material increases durability
Revised piston design helps lower compression ratio to 16.8:1 from 17.5:1
Piston pin bore diameter increased for increased strength
Connecting rod “ I ” section is thicker for increased strength
Cylinder heads revised to accommodate lower compression and reduced cylinder firing pressure
Maximum injection pressure increased from 23,000 psi (1,585.8 bar) to more than 26,000 psi (1,792.6 bar)
Fuel delivered via higher-pressure pump, fuel rails, distribution lines and all-new, seven-hole fuel injectors
Fuel injectors spray directly onto glow plugs, providing faster, better-quality starts and more complete cold-start combustion for reduced emissions
Improved glow plugs heat up faster through an independent controller
Revised variable-geometry turbocharger is aerodynamically more efficient to help deliver smooth and immediate response and lower emissions
Air induction system re-tuned to enhance quietness
EGR has larger cooler to bring more exhaust into the system
First application of new, 32-bit E35 controller, which adjusts and compensates for the fuel flow to bolster efficiency and reduce emissions"
LBZ applications:

Chevrolet Silverado HD
Chevrolet Kodiak
GMC Sierra HD
GMC TopKick

[dwill3015]

This is the LMM specs:


The LMM engines are based on the LBZ engines, but it was designed for US EPA's 2007 emission standards, and uses ultra-low sulfur diesel fuel, which went on sale in the US and Canada in the fall of 2006.[5]

New emission reduction features include Diesel Particulate Filter (DPF). The DPF traps particulate matter, and when the computer senses a pressure differential between two sensors (one located upstream and another downstream of the DPF) the truck enters a "regeneration" cycle. During this time the computer commands the fuel injectors to inject fuel after the cylinder has fired forcing raw fuel into the DOC (Diesel Oxidizing Catalyst) where the fuel is burned to elevate the temperature of the exhaust. This hot exhaust flows into the DPF and burns the trapped soot.

A version was used in Trident Iceni.[6]

Specifications
Engine type: 6,599 cc (6.599 L; 402.7 cu in) V8 turbo
Bore x Stroke: 4.06 in (103.1 mm) x 3.90 in (99.1 mm)
Block / Head: Cast gray iron / Cast aluminum
Aspiration: Turbocharged & Intercooled
Valvetrain: OHV 4-V
Compression: 16.8:1
Injection: Bosch High Pressure Common Rail with CP3.3 Injection Pump
Power / Torque: 365 bhp (272 kW) @3200rpm / 660 lb·ft (895 N·m) @1600 rpm
Code Years Power@rpm Torque@rpm Redline (rpm)
LMM (Chevrolet Silverado HD, GMC Sierra HD) 2007- 365 bhp (272 kW) @3200 660 lb·ft (895 N·m) @1600 3450
LMM (Chevrolet Kodiak Medium Duty (LYE option), GMC TopKick Medium Duty (LYE option)) 2007- 330 bhp (250 kW) @3000 620 lb·ft (841 N·m) @1600 3250
LMM (Chevrolet Kodiak Medium Duty (LRX option), GMC TopKick Medium Duty (LRX option)) 2007- 300 bhp (220 kW) @3000 520 lb·ft (705 N·m) @1600 3250
LMM (Chevrolet Express, GMC Savana) 2007- 250 bhp (190 kW) @3200 460 lb·ft (624 N·m) @1600 3450

[Project Reaper]

wow i wish i knew about diesels lol, thats like speaking a different language almost.

[mrmanners]

This is the LMM specs:


The LMM engines are based on the LBZ engines, but it was designed for US EPA's 2007 emission standards, and uses ultra-low sulfur diesel fuel, which went on sale in the US and Canada in the fall of 2006.[5]

New emission reduction features include Diesel Particulate Filter (DPF). The DPF traps particulate matter, and when the computer senses a pressure differential between two sensors (one located upstream and another downstream of the DPF) the truck enters a "regeneration" cycle. During this time the computer commands the fuel injectors to inject fuel after the cylinder has fired forcing raw fuel into the DOC (Diesel Oxidizing Catalyst) where the fuel is burned to elevate the temperature of the exhaust. This hot exhaust flows into the DPF and burns the trapped soot.

A version was used in Trident Iceni.[6]

Specifications
Engine type: 6,599 cc (6.599 L; 402.7 cu in) V8 turbo
Bore x Stroke: 4.06 in (103.1 mm) x 3.90 in (99.1 mm)
Block / Head: Cast gray iron / Cast aluminum
Aspiration: Turbocharged & Intercooled
Valvetrain: OHV 4-V
Compression: 16.8:1
Injection: Bosch High Pressure Common Rail with CP3.3 Injection Pump
Power / Torque: 365 bhp (272 kW) @3200rpm / 660 lb·ft (895 N·m) @1600 rpm
Code Years Power@rpm Torque@rpm Redline (rpm)
LMM (Chevrolet Silverado HD, GMC Sierra HD) 2007- 365 bhp (272 kW) @3200 660 lb·ft (895 N·m) @1600 3450
LMM (Chevrolet Kodiak Medium Duty (LYE option), GMC TopKick Medium Duty (LYE option)) 2007- 330 bhp (250 kW) @3000 620 lb·ft (841 N·m) @1600 3250
LMM (Chevrolet Kodiak Medium Duty (LRX option), GMC TopKick Medium Duty (LRX option)) 2007- 300 bhp (220 kW) @3000 520 lb·ft (705 N·m) @1600 3250
LMM (Chevrolet Express, GMC Savana) 2007- 250 bhp (190 kW) @3200 460 lb·ft (624 N·m) @1600 3450

I learned something myself. Thank you sir!

[Stealth]

why not make a poll and post this question on it? i want to see what people have and what they think about this topic