I have a 2006 Cadillac STS and I need to change the oil. What is the best quality oil that I can put in???

Mobil 1, syntheticI have a 2006 Cadillac STS and I need to change the oil. What is the best quality oil that I can put in???
Go with a synthetic which I believe that Cadillac recommends Mobil 1. I have used Mobil 1 full synthetic for years and it is an excellent oil. I would also suggest that you use a quality filter (not a quick oil change one). AC Delco makes good filters. I use K%26amp;N 90% of the time in my cars and ocassionally I use Bosch filters which have good quality at a very reasonable price. I think with the STS the computer will tell you when to change the oil if not I would go about 6500 before changing it. To be 100% sure on your change interval take a sample of your oil at 5 to 7k miles and then send it in to Blackstone Laboratories and they will analyze it and send you a comprehensive report on the amount of additives left in the oil and the contaminants in the oil. I have also used Royal Purple %26amp; Pennzoil synthetics and can recommend those as well.I have a 2006 Cadillac STS and I need to change the oil. What is the best quality oil that I can put in???
You have 3 options. Mobil 1 synthetic, Valvoline synthetic, or Castrol synthetic. They are all there basically the same. Anyone want to argue that ignore them. They all buy the same additive package from the same company. DONT USE PENSZOIL!
MOBIL1 FULL SYNTHETIC!!!
mobiel one is the best that is what they use in the corvettes.