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absinthminded
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white1500
white1500

I find it so odd that a clean 00-02 still attracts me way more than any gmt900 ever could, and than the K2's currently do.   I see a well kept black 99-02 Silverado every 2 weeks that looks identica

hockeypro1411
hockeypro1411

I beg to differ on ALL of that.. The build quality of the 900's will never be as solid as the 800's. With fuel economy requirements and such, the thinner and lighter materials make it impossible. In m

Justin_Denton
Justin_Denton

I have an 04 Silverado LT with 102k that I got in 06 and haven't had any problems with it. Just rebuilt the entire front end and did brakes last year. I want a new one but love not having a payment.

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Chris Senior Enthusiast

Chris

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Posted

On the outside, nothing. On the inside you have 41 more cubic inches. Longer stroke so more torque, larger bore more HP. Your 5.3 is rated 285/325, my 6.0 is factory rated 345/385. I have the "High Output" version from the Silverado SS/Escalade/Vortec Max/05-07 Sierra Denali

Badass69 Senior Enthusiast

Badass69

Posted
Posted (edited)

And the LQ4 is severely under-rated...... even in stock form in the Denali Suv's and such it was 325/330 HP and 370 lb ft versus the 300 HP and 360 lb ft in the HD's.... What's the difference? The HD's have power enrichment delay that the light duty trucks do not...... and...... the LQ4 in the HD is rated at 4400 rpm only whereas in the light duty stuff it was rated at 5200 rpm like the LQ9. Funny thing is in stock form an HD still revs to 5200 rpm WOT shifting lol. The LQ9 has a better tune, but not by a lot. Either engine properly tuned will make your 5.3 feel lethargic... even if it's tuned. 44 cubes, better heads and the 4" bore do that....

 

The only difference between an LQ4 and a LQ9 is flat top pistons in the 9 giving it the 10:1 compression ratio versus the 4 at 9.4:1. 04.5 and older LQ4's have weaker press fit pin rods... but 04 and a half model year and newer they have have the same heavy duty floating pin rod the 9 used.

 

Swapping a 5.3 for a 6 liter is a great investment no matter how you look at it.

 

I have both LQ4's and a LQ9...... my LQ9 makes a nice lawn ornament currently lol.

Edited by Notamember
Chris Senior Enthusiast

Chris

Posted
Posted

The 04 up 9's have better connecting rods as well. I had an aggressively tuned 4.8 and I would never go back to anything under 6 liters again

Badass69 Senior Enthusiast

Badass69

Posted
Posted (edited)

The 04 up 9's have better connecting rods as well. I had an aggressively tuned 4.8 and I would never go back to anything under 6 liters again

 

LQ9's have had the heavy duty rod from the start excluding some early 2002 model ones. All LS engines ( 4.8-6.0) got the better rods mid year 2004.

 

We verified that with an early 2003 model LQ9 from an 03 Escalade that still had the small 10 mm head valley cover bolts on it ( although not gospel the 13 mm valley cover bolts generally indicate the floating pin rod) and it had the full floating pin rod. It was original too as the mid year shift of 2004 changed the head bolts from unequal length to equal length. This LQ9 had the old style unequal length head bolt arrangement.

 

Really guys call the rods LS2 rods which is honestly incorrect. The connecting rods existed 2 years before the LS2 even made it into production.

Edited by Notamember
Chris Senior Enthusiast

Chris

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Posted

I just know what I gathered over on silveradoss.com

Badass69 Senior Enthusiast

Badass69

Posted
Posted

I just know what I gathered over on silveradoss.com

 

Eh... I rip them apart myself to make sure lol. I had read both ways on the interwebz and then it was pretty well maintained on pt.net that the LQ9 had the rods all along.

 

That 03 with the old style unequal length head bolt block verified that.

kstruckcountry Senior Enthusiast

kstruckcountry

Posted
Posted

Nothing is as cheap as keeping what I have. And judging by how good this motor runs with no tick and no oil consumption it will be good for at least another 100k.

 

Fortunately one of my friends is going to build a go fast truck, so helping with that will be fun.

absinthminded Enthusiast

absinthminded

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Is there a lot of after mkt supoport for the LQ9? Headders, rods and pistons ect? I'f I was going to do it I would want to freshen it up and add boost. This is pretty much the only forum I look at concerning trucks. I'm not well versed.

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