gpr

iTrader: (6)

I found a guy selling a 2005 5.3 that he says is out of a trailblazer, and that it is aluminum. Would this be a L33? How do you tell?

Also it doesn't have wire harness or pcm. I'm assuming if it is still a Gen III motor any wire harness with knock sensors under the intake would work? (i will be cutting it down anyway for the conversion) and that a 411 pcm would work? If its a 2005 is it still a 24x crank?

HexenLord

Yes it still uses a gen 3 harness/ECU and its a 24x.

If its an L33 it'll be all aluminum and have 799 or 243 heads. If its aluminum without either of these heads, its likely an LM4.

I wasn't aware the L33 came in a Trailblazer.

gpr

iTrader: (6)

Isn't an lm4 the engines with shorter crankshaft snouts using in fwd cars? How do you identify this by looking at it?

HexenLord

LS4 was the FWD engine.

gpr

iTrader: (6)

Ok, thank you for your help. Not sure if wikipedia is correct but it is showing that a 2005 trailblazer had the LM4 in 2003-2004 and a LH6 2005-2009. So with that being said the LH6 (aluminum version of lm7) is a gen IV motor, thus i would need to get a wire harness and pcm for this platform, correct? Also I'd assume is the 58x crank, and i guess i would also need a throttle pedal?

I'm more familiar with tuning the dbc engines. Would I be able to use an older pcm and wire harness to control the newer dbw? Or I have a spare fbody stock throttle body, could i put that on the newer engine?

I'm trying to figure out what I need to transplant it into a chevelle. Like stated I'm familiar with tuning the Gen III engines, not much on the Gen IV.

gpr

iTrader: (6)

Also is there a way to identify these Gen IV engines? They guy didn't seem all that confident on the information i was getting from him.

Sean At CBM

Generation IV

First introduced in 2005, the Generation IV Vortec 5300 engines share all the improvements and refinements found in other Generation IV engines. At present, four versions of the 5300 engine in production: 2 iron blocks (LY5 and LMG) and 4 aluminum blocks (LH6, LH8,LH9 and LC9). All versions feature Active Fuel Management except for the LH8, LH9, LMF.

LH6
The Vortec 5300 LH6 (VIN code "M") with Active Fuel Management replaced the LM4 for 2005, and was the first of the Generation IV small block V8 truck engines to go into production. The LH6 produced 300 hp (220 kW) and 330 lb·ft (447 N·m). It is the aluminum block counterpart to the LY5.

LH6 applications:

2005–2009 Chevrolet TrailBlazer including EXT (through 2006)
2005–2009 GMC Envoy Denali
2005–2006 GMC Envoy XL
2005 GMC Envoy XUV
2005–2007 Buick Rainier
2005–2009 Saab 9-7X
2007 Chevrolet Silverado 1500
2007-2009 GMC Sierra 1500

M6 Swap

iTrader: (1)

this might be a dumb ? but how do you identify which pcm you have? Which number is the part # on these things?

91FormulaKiller

iTrader: (28)

If you're referring to GEN III, its the service #, example being the last 4 of the most popular ECM used is "0411"

Bilster

iTrader: (21)

Here are a few casting numbers....

Sorry...this PDF file is small. Boost the text to a magnification of 150%.

The 2005 Trailblazer has a L33 with a casting number 12562735. That is if it has this casting number.

91FormulaKiller

iTrader: (28)

The pdf list blister just posted says an L33 from a trail blazer is gen iv(which seems off to me), 05 06 full size truck L33's are gen 3 which is easier to work with.

91FormulaKiller

iTrader: (28)

Best way to end all doubts is pull the pan off and check the reluctor ring, check for 24 or 58x. I would do this nowadays anyway since some people swap a 58x over to 24x.

Bilster

iTrader: (21)

I noticed that too. I just took that off the Summit Racing website. You are correct...best to just check the crank sensor. Black is 24 and I believe grey is 58. Or as you stated, check the reluctor.

I have an LM4 which is aluminum also...but without the flat top pistons. Mine are dished and my head bolts are still long. It's a 2004 and probably the last year of the Gen III.

One cool thing about the aluminum 5.3s is their casting is LS6 with the added webbing for strength and the better bay to bay breathing. What makes that so cool is you can bore AND torque plate hone to stock LS1/LS6 bore size for a perfect bore. Even the new LS1/LS6 blocks were not torque plate honed at the factory. Plus a used 5.3 has already done a few heat cycles so any core shift is completed so your newly torque honed bore will remain true.