I've been running Amsoil 5W-30 in my '99 Buick Regal for the past several of years. This car has the supercharged 3800 and has been mildly modified. It was custom street tuned and runs perfect at all RPMs. The car sees almost 100% interstate driving and very little full throttle use. I currently change the oil at 10K mile intervals using Wix filters. I will typically use about 1 qt of oil in 10K miles. The one UOA I did on it was on a 7500 mile interval and showed the oil good for continued use.
I'm tired of having to mail order Amsoil and want to go to a locally available off the shelf oil. I'm favorable to both Mobil 1 products as well as Penzoil Platinum. I use PP 5W-30 in my van and am very happy with it. It runs great and doesn't use a drop. Do I need a little thicker oil in the Regal, or not sweat the 1qt in 10K miles that it uses. What would you recommend?
I'm tired of having to mail order Amsoil and want to go to a locally available off the shelf oil. I'm favorable to both Mobil 1 products as well as Penzoil Platinum. I use PP 5W-30 in my van and am very happy with it. It runs great and doesn't use a drop. Do I need a little thicker oil in the Regal, or not sweat the 1qt in 10K miles that it uses. What would you recommend?