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Pelado
05-28-2010, 14:48
In a couple of days I´m going to check what it can be a Duramax engine from a salvage yard.
Duramax engines are almost non existant down here, only forme US embassy vehicles.
The guy from the salvage yard don´t have a clue at what he has there, he told me it´s a 7.3 TD v8 with 440Hp from a Chevy 2500 Crew Cab.

How can I identify if it´s an LB7, LLY or what?

NutNbutGMC
05-28-2010, 15:17
In a couple of days I´m going to check what it can be a Duramax engine from a salvage yard.
Duramax engines are almost non existant down here, only forme US embassy vehicles.
The guy from the salvage yard don´t have a clue at what he has there, he told me it´s a 7.3 TD v8 with 440Hp from a Chevy 2500 Crew Cab.

How can I identify if it´s an LB7, LLY or what?You are correct. The guy at the salvage yard is clueless. The reference to a 7.3 litre is a Ford Powerstroke diesel.

I will say this as an opinionated response. Do not consider an LB7 due to the repeated failure of injectors and related components. $0.02. There are more threads here about this issue than I can count.

Engine Identification:

The Duramax engine has evolved from the original LB7 series to the LLY, then LBZ, and now the LMM series. The LB7 was used from 2001 model year until mid 2004 model year. In mid 2004 the LLY series was released. In 2006 the Duramax changed again. The early 2006 engines were still called LLY and the later 2006 and 2007 "Classic" became the LBZ. This creates some confusion as the 06 LLY is distinctively different from the 04.5-05 LLY. The 2006 LLY and LBZ engines are essentially the same when it comes to modifications. The LMM began in the new body style GMT 900 series trucks in 2007. The simplest way to verify which series you have is the VIN# of the truck. The 8th digit is the engine ID and it will either be a 1, 2, D, or 6.

01-04 LB7 is a 1 Horsepower 300 / Torque 525 ft-lbs
04.5-05 LLY is a 2 310 / 610
06 LLY is a 2 (uses same mods as LBZ) 310 / 610
06-07 LBZ is a D 360 / 650
07.5 - 08 LMM is a 6 (new body style GMT 900 series) 365 / 660Example: 1GCHK29143Exxxxxx for LB7 and 1GCHK29245Exxxxx for LLY. It is important to know this as while the engines are essentially the same at the core, the electronics, turbochargers, electronics, and injectors are different among the variants. The 10th place in the VIN number identifies the model year on these vehicles. The example above shows the 2003 model year LB7 and 2005 LLY.

Cite: http://kennedydiesel.com/