NOTHING!!! Just regular servicing.
Excellent car! It has been on many trips and has never quit. It is comfortable and has more power than ever!
With 255,000 miles on it, however, it is starting to fail. It burnes oil, leaks antifreeze, and smokes. But it has been a wonderful car and worth every penny!
It is by far in a distant mile from a basic Toyota or Honda, I have a '95 Century that has been across country twice and all I do is just maintain it and and yes I do get lazy, but I do take in for maintenance. It just goes and has 92,000 miles and feels like it did new, GREAT CAR!! Unlike those harsh Hondas, Camry or Fords and Dodge.
I realy love this car on endurance!!
Got to love it!, it is cheap, easy to maintain, with a big v6 for its size. It has 100k miles, but starts right up as it did 12 years ago! These cars are know to go 200k+ during its lifetime, as long as you maintain it on time, though the GM paint don't shine for long, I just got it painted and it looks good, highly reccomended for anyone who wants a reliable and affordable car! a++