Oil and filter change... best oil???? additive???

[92GrandprixSE]

I just bought a 92 Grandprix Se but it almost has 180,000 miles on the engine. The engine sounds good but i want to protect it as much as possible. Any recomendations on type of oil i should use....What weight should I use? Should i use any type of engine additive???
All help very much appriciated.......Thanks alot

[Ripn12s]

I'd say stick with whats in it or maybe one of those high mileage oils.

Id say not to use synthetic and if you do expect oil leaks.

[GTP Jeff]

You want the BEST oil.. It's Royal Purple.. The best filter (redially avilable) Mobil 1..

But with 180,000 on the clock, I wouldn't bother.. The high mileage stuff thats on the market will help to keep your seals pliable.. Thats your main concern..