Eventually, once I save enough money (which could take a while since I am getting married next month ) I would like to swap out my 5.3L to a 6.0L.
Since I am ****, I am already researching everything involved, and I came across the fact that 5.3 engines came with aluminum heads and 6.0 engines came with iron heads. Why would GM do that? Which ones flow better and what other differences were there?

Thanks for the edumucation

 

First off, welcome to the site! There's a lot of great info and awesome folks here to help you out The 6.0 engines only came with iron heads in 99-00, then in 01 they switched to 317 casting aluminum heads. In stock form, the 6.0 heads flow better than the 5.3 heads, but 5.3 heads will allow for more compression when bolted on to a 6.0. You can search this section using keywords similar to your thread title and you'll find oodles and oodles of info

*EDIT* Moving this to the internal engine section to help your search, as when I referred to "this" section

 

Also note, that the engines (6.0's) that had the iron heads also had a longer cranks shaft, which makes things a pita to install, if getting matted to a 4L60e trans.. Best bet is to not even consider a iron headed 6.0

 

Thanks for the response guys, that helps out

FYI, I have been a member of this site for 5 years, but have been mostly a lurker.
I havent done much to the truck...but now that i am past the 100K mark and my warranty is expired, eff it LOL

 

Yea, and now that you're active and posting, we'll have you spending your paycheck on your truck real quick lol

Wow, a member since 05, I didn't even notice that when I welcomed you to the site! That's a lot of lurking lol