05-28-09, 10:35 AM
Debating on a 99STS an 02 Deville, both in excellent condition with no problems. Both well over 100,000. I've had several caddy's in the past 3 years an a mechanic an with the help of this forum learned alot. I know they improved the headgasket issue in 2000, but how much. It seems the 99's an earlier are popping up everywhere around here on craigslist an etc for sale with blown headgaskets. Seems like a 25% failure rate to my estimation. I know there's no engine thats immune to headgasket failure, but are the 2000 an up a whole lot better?
05-28-09, 10:58 AM
2000+ saw a change to roller cam followers, a head redesign, and a change in the block metallurgy. Along with that came a series of head bolt thread and length changes, with the 2003 FWD series having the longest head bolts with coarser threads.
There's quite a "car" difference between a STS and a base Deville, so that should figure in your search also, but personally, I would hold out for a late (post 02/02) 2002-3 STS. The later STS series has the Magnetic Ride Control system used by Corvette and Ferrari then, and is in some GM lines now. (If your used car deal is, compared to others of the same model, too good to be true, something's fishy. You will pay top dollar for a cream puff. There's no needle left in the haystack here..............)