I think synthetic oil is a great idea. Go with a true synthetic, and not a blend. Mobil 1 seems to be the favorite, although I've heard very good things about Royal Purple's synthetic oils. Too expensive and difficult to obtain for me, so I use Mobil 1 0W-30 or 5W-30 depending on my mood. No need to change it till 5-7000 miles, so it pays for itself.
No need for fuel additives. Just run decent gasoline.
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