L33 was only offered in 05 and is an aluminum block HO 5.3. Check your RPO codes in the glove box and look for L33 or LM7...

 

I have the Z code engine in my truck apparently from what the vin number says. From what i know that is the FLEX engine right? Did they make an L33 FLEX?

 

What's the complete vin minus the last 6 digits?

 

Look at the head cast #'s..The l33's had 799 heads in the gmt800 trucks

 

Alright, I'm at work right now but when I get off ill look. Where at on the head will this number be and what will the number be? will it just say 799?

 

Yes, it will just say 799 on the corner of the head. For example passanger side in front, on the corner, Right behind the tensioner and nest to the water pump.
I think you should run it tell it blows. Hell might be 3 more years. Then it gives you a reason to put a 6.0 in or if you saved enough mine as well throw in a LSX block and build a beast.

 

Alright ill check when I get off. Hopefully that will be the case, atlwast that will explain some things.

 

says 708 on the head.

 

As far as the vin goes its a1GCEC14V65Z. that's minus the last 6 digits.

 

Your VIN engine code = V

4.8L LR4

The 'Z' is your plant code. Fort Wayne, Indiana.