57chevyragtop,
Looking at my records, my '02 started having coolant issues at 67,650 miles ("LOW COOLANT LEVEL" warning message appeared for the first time). Before that, I was constantly monitoring the fluid level and checking the engine for any signs of external leakage because I was told that "they all leak" (which I didn't believe at first ... now I do). One thing that did concern me back then (and which now I know is a leak) was the dampness along the black "V" seal behind the power steering pump. This dampness turned out to be a very slowly-developing leak because now I can periodically see tiny bubbles from the dye I had poured in last year popping out of this seal - and just below is some (perpetual) "mud" - which I now know is an accumulation of road sand mixed with trace amounts of coolant. Interestingly, yesterday I went out to lunch with a few co-workers. The guy driving had a company car: 2005 Impala 3.4. So I popped the hood to inspect his engine. Guess what? Same dampness in the same spot. So the problem is very likely beyond the 2001-2003 model years that everyone talks about! The only difference might be that the later model year Impalas (post 2003 - which supposedly have the better gaskets) might have to be driven harder or longer to make the problem manifest itself. I've driven my Impala almost 20k miles per year so far and the company car Impala is around 30k+ per year. If you're just driving around town, maybe you can ride (apparently) "problem-free" in a 2001-2003 Impala for 7 years or so (my Dad, an around-town only driver, has a 2003 Impala with around 50k on it and so far no complaints of missing coolant. But then again his mechanic let a Taurus coolant system corrode to the point where three freeze plugs rusted out - one behind the tranny that cost $700 to replace! Hmmm ... is that dishonest or incompetent?).