LQ4 & LQ9, What is the differences between the two
 

What is the differences between the LQ4 and LQ9 engine??

If I am not mistaken an LQ4 is a 5.3 engine. The LQ9 is the 6.0. I am sure somebody else can elaborate.

Damn I was hoping to find some answers. I was wondering the same thing.

I'm not sure but I believe that the LQ9 has flat top piston giving it more comp. I'm pretty sure that the cam, heads, mani, etc are all the same.?

Someone with more knowledge please chime in.

LQ4 & LQ9 are both 6.0 iron block aluminum head. (Early LQ4s had iron heads)

both lq4 and lq9 are iron block 6.0s 5.3's are LM7/LM4/L59/L33
i dont believe there are majors differences between the two maybe some block webbing and sensor locations

from what i know the lq4 is an aluminum block and the lq9 in an iron block.
i have the lq9 in my 04 escalade ext and the powertrain in the truck is simular the the silverado ss.
my ext has the awd and the ho 6.0 345hp

its mainly just the difference in compression. If your wanting a boosted application go for the LQ4

Im pretty sure an LQ4 is an iron block with lower compression that comes in the chevy pickups. The LQ9 is the higher compression motor that came in the Escalade. Both 6.0 liters.

Wow, a lot of misinformed responses. A quick search would have netted you the correct answer, but to clear the air with facts:

LQ4 and LQ9 are Gen3 engines, not Gen4 (like the LS2, LS3, L76), due to the location of the cam sensor and knock sensors.

LQ4 debuted in 1999
Displacement was/is 6.0L
1999-2000 had iron heads
1999-2000 had a crank adapter to mate the LQ4 with the 4L80 trans (not LS1 compatible)
Compression ratio was 9.5:1
Bloack was Iron

In 2001 the LQ9 was introduced
Both the LQ4 and LQ9 shared the iron block and new 317 heads (similar as the 243, but with larger 76cc chambers), hence both are 6.0L
The LQ9 had 10.4:1 compression ratio, versus the LQ4's 9.5:1
No longer did either 6.0L require the crank adapter for the trans, now works with LSx applications.
In 2004/5 6.0L recieved improved rod design

In 2005 the LS2 block was introduced
It is essentially the LQ9 with an aluminum block
LQ9 still offer with an iron block.

I was closer than I thought.

Good information instead of guessing :chug:

Great info, thanks guys.

So I was pretty much correct.

THREAD JACK: sorry

Now my question is: How many cc's is the dish in the LQ4 piston.
I'm trying to figue how much comp a stock LQ4 with 243 heads will have.
https://ls1tech.com/forums/new-ls1-owners-newbie-tech/1009359-ls2-cam-ls1-lq4.html

I will have to look at my notes at home, but if I remember correctly it should be 10.4:1, similar to an LQ9.

That would be much appreciated. PM me.

THREAD JACK over.

Wow, information, this is great, my wife is going to hate me for a while since now I am going to be studing all this stuff everyday.

Question on the LQ9 all aluminum engine, does anyone know what kind of HP this one comes with from the factory?
Just had a friend stop by and we were talking about these motors and he said he might know where a 6.0L with aluminum block is for sale with harness and computer, are these good motors??.
I have heard from one guy on the net who told me to stay away for the DoD motors, how can you tell them apart?

The only aluminum 6.0 motor is the LS2. The LQ4 and LQ9 truck motors are iron blocks.

The L76 and LY6 are aluminum 6.0L truck motors that replaced the LQ4 and LQ9. Not saying you are wrong, just adding info. :)

OK, so the LQ9 is has a composite/carbon fiber block, while the LQ4 is made of titanium. I think I got it now. :D :D :D :D **kidding**

I believe the LQ4 pistons have a dish just over 8cc's. The LQ9s have flat-tops which (I believe) are the same as LS2s.

Wow, a lot of misinformed responses. A quick search would have netted you the correct answer, but to clear the air with facts:

LQ4 and LQ9 are Gen3 engines, not Gen4 (like the LS2, LS3, L76), due to the location of the cam sensor and knock sensors.

LQ4 debuted in 1999
Displacement was/is 6.0L
1999-2000 had iron heads
1999-2000 had a crank adapter to mate the LQ4 with the 4L80 trans (not LS1 compatible)
Compression ratio was 9.5:1
Bloack was Iron

In 2001 the LQ9 was introduced
Both the LQ4 and LQ9 shared the iron block and new 317 heads (similar as the 243, but with larger 76cc chambers), hence both are 6.0L
The LQ9 had 10.4:1 compression ratio, versus the LQ4's 9.5:1
No longer did either 6.0L require the crank adapter for the trans, now works with LSx applications.
In 2004/5 6.0L recieved improved rod design

In 2005 the LS2 block was introduced
It is essentially the LQ9 with an aluminum block
LQ9 still offer with an iron block.




thank you very much to the guy who posted this thread and to the guy who posted the above information. I have a 2007 60 lq4 and I was getting on tonite to ask a question regarding parts interchange between my engine and ls blocks. If I am understanding correctly I will be able to use parts like intake, heads, water pump,ect. from any ls2 engine. Will I be able to use an earlier model 5 or 6 speed manual like out of out of an 99 or 2000 camaro behind my engine? please post any helpful responses.

What "crank adapter" are you speaking of with the LQ4?


I put on right in place where an LS1/M6 was with no issues at all. Just remember a pilot bearing........