Does anyone know what the differences are in the 2007/20008 5.3L LMG and the 2009+ LMG engines are? I have a 2008 Silverado with the 5.3L LMG and all the interchanges say that only an 07 or 08 engine will work. Does anyone know what changed in 2009 and why the engine wouldn't be compatible? It's a lot easier to find a lower mile 2009 or 2010 engine.

 

maybe its the vvt/dod.

 

i had a 2002 z28 6speed.

 

2010
320 hp ( 239 kW ) @ 5400 rpm SAE CERTIFIED ( gasoline, as tested )
326 hp ( 243 kW ) @ 5300 rpm SAE CERTIFIED ( E85 Flex Fuel, as tested )
Chevrolet Avalanche 335 lb-ft ( 454 Nm ) @ 4000 rpm SAE CERTIFIED ( gasoline, as tested )
Chevrolet Suburban 348 lb-ft ( 472 Nm ) @ 4400 rpm SAE CERTIFIED ( E85 Flex Fuel, as tested )


2009 was the 1st year LMG was available on the GMT900 trucks, 07+ LMG was available on the F/S SUV's like Avalanche, Yuke and Hoe.

2010+ LMG got VVT for the 1st time. The torque peak is at 4000rpm in 2010 vs 4400rpm for the 07-09 LMG. 2010 LMG was the 1st LMG to get power/torque ratings with BOTH gasoline AND E85 fuels.

2008 LMG
315hp@5200rpm 338lb/ft@4400rpm

2010 LMG
315hp@5200rpm/335@4000rpm on gas
326@5300rpm/348lb/ft@ 4400rpm for E85

These ratings are using the newer SAE CERTIFIED power, so I don't think GM could be manipulating ratings of the 2010 LMG simply to promote E85 equipped vehicle sales like some have inferred. Gm could have simply made the tune a but hotter on E85 than gasoline, but a ringer calibration ONLY for testing wouldn't be happening.

peace
Hog