[Cliff8928]

The OE Double Platinum plugs on the Ecotec should last the advertised 100,000 miles (they should for like $6/ea). I pulled a set of original plugs from a lincoln my dad had with 80,000 on the originals and they weren't even that far off in the gap (maybe .001")

The service life of the antifreeze is 5 years, 150,000 miles (whichever comes first)

GM is using a new rubber material for the belts and hoses which is significantly more durable than the older materials, those should last the 100,000 as well.

I'm sure I'll have to do an oil change soon, I've got like 5,500 miles on it already (the change oil light didn't come on yet)