I have had three 5.3's. One was in a 2000 suburban that I recently retired. Engine still runs great but with all its other issues and rust, it's not worth bringing back again. Has 360,000 miles on it. I owned a 2008 suburban also for a short period of time. It had 130,000 miles on it when I sold it and it burnt oil like crazy. Like a quart every 1,000 miles. Due to that cylinder deaction ****. Funny thing is when I bought it, the last thing i was worried about was the engine. That's why research is so important. I didn't research. If you research those first few years of the 5.3's that cut cylinders you will see it's a common problem. And lastly my 2004 gmc yukon has a 5.3. Now that's another thing about 5.3's. At around 220,000 miles I started going through antifreeze pretty bad. It took me quite awhile to figure out that it had a cracked head. There were some poorer cast heads in 04 and 05. So that's another thing to pay attention too.
On a side note, I dumped in a bottle of stuff (I forget the brand) that can supposedly seal those really hairline cracks. Amazingly it has worked. I have put on 30,000 miles since and it has not used a drop of antifreeze since.
So yes, there are quite a few difference from one year 5.3 to the next.
