I'll throw some more chaos into this discussion......in theory only the '02+ LQ9 had the flat-top pistons, but both JERRY2500 and I have flat-tops in '99 LQ4's that came with iron heads. I'm pretty sure (but have NO proof) that '99-'01 LQ4's came in a few different varieties and the GVRW you have is what determines the flavor you got from the factory (this is MY theory...I have NO proof but it seems to bear out pretty good)

 

My 2500 hd was gm exec, driven until bought it as 2nd owner behind gm. Gm records show no engine changes during their ownership. the ride has always had 317 alum. heads, and is currently on the bench with full float factory rods exposed. also, has the right numbers in the vin for lq9. A knowledgable goodwrench will tell you that there were a few out before the end of '01. Guess I got lucky. But who cares anway, the stroker begins assembly next week. .

 

All aluminum heads on the 6.0 in trucks are 317. LQ9 were only in the SS and Cads. I have been building them since 98. The difference on them are rods, pistons, oil pump, and intake. Also some of the outside parts like coils and exhaust are different.

 

GM has 3 rods for the gen3 motors. The 4.8 has it's own rod unique to only it, all other's except the LQ9 (5.3, 5.7, and the LQ4 6.0) use the same rod, the LQ9 has it's own rod as well.

 

didnt the LQ9 also come in some denailis and VHOs

 

can you take a picture of the RPO tag in the glove box?

 

The LQ9 is standard in the VHO.

 

like i said some denailis AND VHO. i didnt say some VHOs i said and VHOs

 

my bad, maybe it would have been more clear as "some denali's and all VHO's"

 

I am pretty sure the Denalis got the 325hp lQ4 engines and not the 345hp Lq9. The GMC C3 and the GMC Denali AWD pickup were rated at 325 hp and 370 lb/ft of torque.
The 2004-2006 VHO B4V 1500's as well as the 2006 Vortec MAXX got the Lq9. the VHO's got the 4l65e and the Vortec MAXX got the 4l70e.

peace
Hog