Cylinder head casting number for 5.3?

[xx_gearhead_xx]

I got into a debate with a friend on which cylinder heads come on the 5.3 in the TB's. I couldn't find any pictures of what I was looking for, but I thought I remember reading the early 03-04 models out of the ext's had 799 heads. Then, the 05 and up 5.3's had the 243 heads, can anyone confirm this?

 

[xx_gearhead_xx]

Anyone got a 5.3 360 or 370 they can check?

 

[RedRocketZ28]

The early 5.3's had either 706's or 862's unless it was a "L33 HO 5.3" which only came in some trucks. My 04 Rainier has 862's, my 02 Avalanche had 706's. The 243/799 heads are one in the same, excluding the 243's that came on the LS6 motors as they had hollow stem exhaust valves and better springs, but everything else casting wise was the same.

The 243/799 heads came on the 5.3 "L33 HO" motor in 05. The 5.3 "LM4" is what I have in my Rainier and it had a short production run and was used in the 03-04 GMT360 vehicles and the SSR. It is an aluminum block 5.3 with either 706 or 862 heads, NON DOD. The 05-09 GMT360's got the LH6 and the 07+ will more than likely have 243/799's.

In 07+ all the 5.3's started getting the 243/799 heads. The early years will obviously depend on what 5.3 equipped vehicle you have. Here's some more info...

https://en.wikipedia.org/wiki/GM_small-block_engine#5.3_L