slipstream444

Just a side note on this - while Mobil 1 EP is a good oil (and notably better than standard Mobil 1) , there are a few other synthetic oils that are better, and in the case of Amsoil 10W30 (ATM) specifically and measurably better in every industry metric. Redline synthetic (which is a group V synthetic) is also better.
According to every unused and used OA that I've seen to date, Amsoil starts with and sustains a higher TBN throughout its life-cycle (12.2 from the start), demonstrates lower wear, is much more stable (with the lowest NOACK available on the market at 5.4), and stays shear stable (better HTHS numbers) and within its rated viscosity longer than any other 10W30 oil I've seen. Mobil 1 EP and Amsoil ATM have the lowest borderline pumping temperatures on the market for a 10W30, and both have a pour point of -54F.

Valvoline Syn Power seems to be another good synthetic oil that performs well in industry standard tests. It's not as good as Amsoil or Mobil 1 EP, but like M1 EP it's a vastly improved oil. It actually comes very close to M1 EP in almost every area (with the exception of unused TBN - it isn't designed as an extended drain oil) and outperforms M1 EP in the anti-wear department.

ATOice

I change my oil too often to go to EP, but I use the EP in my daily. The S gets about 500 miles to each oil change. My DD has no problems with the EP and I have used it for over a year.

my_slow_2k

Is this a typo? Did you mean 5000? I would really hope 500 is not your interval, I guess unless of course it is a straight track setup?

JackS

Good info on the Mobil 1 Syn versus M1 EP. I always assumed that the EP probably had some added binders to prevent blow-by when used in older engines. My future purchases will be M1/EP.

JoeyBalls

I just made the switch to AMSOIL 10w-30, thinking about moving to a 40 weight for the summer, bad idea?