Can you tell me the basic differences between the LB7 and LLY Duramx?

Welcome to the forum. One of the big differences between the 2 is the LLY's injectors are accessable for repair without removing most of the upper half of the motor. They run through the valve covers, not under them. Then there's the variable vane turbo, an extra 5 hp, plus more torque. For more details try using the search feature on this site.

Take a look at this link:


http://www.thedieselpage.com/duramax/lly2004.htm

10 more hp and loads more torque.


They just run circles around the LB7 http://www.dieselplace.com/forum/smileys/Big Smile.gif








This ought to liven up this thread http://www.dieselplace.com/forum/smileys/Big Smile.gif


PBI installed, let the flaming begin.

10 more hp and loads more torque.


They just run circles around the LB7 http://www.dieselplace.com/forum/smileys/Big Smile.gif


This ought to liven up this thread http://www.dieselplace.com/forum/smileys/Big Smile.gif


PBI installed, let the flaming begin.





Well I've driven both extensively and know the real truth so you wont get me too riled.


What YOU should be concerned about is the fact that the LLY is supposed to beat the 6.0 with the same turbo, yet the 6.0 will walk on by the LLY. ..... when its running of course http://www.dieselplace.com/forum/smileys/HiHi.gif

Or when it's being towed by another Duramax!http://www.dieselplace.com/forum/smileys/Evil Smile.gif

Or when it's being towed by another Duramax!http://www.dieselplace.com/forum/smileys/Evil Smile.gif


Or when it's being towed by another Duramax as the Duramax pushes a CTD out of the way... Even my LB7 can do that...http://www.dieselplace.com/forum/smileys/Clap.gif

Upgraded glow plugs i believe, the LLY is not available with the manual transmission, you must have the allison to have the LLY. LLY went into production around christmas time this year and can be identified by VIN #. 8th digit is a 1 = LB7 digit is a 2 = LLY. Injectors, turbo and a few other minor things that i forget but im sure you could find by doing a search on this site. LB7 300hp/525tq LLY 310hp/590tq

Can you tell me the basic differences between the LB7 and LLY Duramx?



WELCOME Evilcody,


2004 LLY Duramax has the following:

Fuel pressure regulator:
Internal design change and external wiring connection change.

Fuel rails:
Design change to incorporate fuel pressure sensor and pressure limit valve in or on the rails.

Fuel injector:
New CRIN 2 Bosch design and injector orientation has changed to outside of the engine.

Fuel pressure sensor:
Higher pressure reading ability and sealing method changed to bite type seat.

Fuel injector return lines:
New design external to engine.

Fuel pump:
Adapter flange new design with vent, new KUEV valve settings.

FICM:(Fuel Injection Control Module)
Cooling plate change, CRIN 2 software.

ECM:(Engine Control Module)
New Delphi processor.

Cylinder Head:
Includes integrated injector tubes and modified intake port locations.

Valve Cover:
New design to accommodate injectors moving outside of the engine.

Serpentine Belt:
New material.

Turbocharger:
New VVT design from Garrett

EGR Valve:
New design controlled by DC motor and new supplier EGR cooler.

HP fuel line routing:
High pressure fuel line routing has changed due to the removal of the Function Block.

PCV System:
Design changed from open system to a closed system with fewer parts.

Intercooler design with plastic tank ends.

Glow Plugs:
New design low voltage 4.7V PWM control

Glow Plug Controller:
New design fast glow controlled by CAN, pre and post glow.

Cam Sensor:
New design and supplier Denso.

Crank Sensor:
New design and supplier Denso.

VPS:(Vane Position Sensor)
VVT turbo control.

Turbo Control Solenoid Valve:(Vane Position Sensor)
Additional component to actuate VVT turbo.

New design starter

Intake Air Heater and Function Block are gone.

Heads, High Pressure pump and injectors are specific to 2004-up engines.

3500LLY, all the motors are LLY, only derated for manual trans apps.


The super fast glow plugs are a nice feature and don't even cycle in warmer weather or warm motor.

I was wondering that. The hp/tq numbers are still the same as the LB7 if you buy the manual. Do you still get the rest of the things stevenorcal listed when you buy a manual?

Yes, look at your engine code, even the injectors.


All LLY are same except for the power settings.


I wonder if u put a Alli ecm in it if it would give u the extra power?