Let's say you're using M1 0w-30 in a non-turbo, with severe driving conditions. How fast can it thin out and need to be changed? If it was mixed 3-1 with M1 0w-40, would the change interval be extended?
M1 0w-30 seems to be very shear stable if you look at the UOA reports on it. In fact, according to an SAE paper published by Mobil, it may be their most shear-stable 30-weight. I think the oil's weakness is volatility not shear stability.
quote: Originally posted by Jay: M1 0w-30 seems to be very shear stable if you look at the UOA reports on it. In fact, according to an SAE paper published by Mobil, it may be their most shear-stable 30-weight. I think the oil's weakness is volatility not shear stability.
HTHS is one spec. In the SAE paper, 981444, Mobil has a lineup of several oils. I'm reading from a shear stability chart where they are using test method CEC-L-36-A-90 to evaluate the oils:
The first 4 oils are PAO/ESTER synthetics, presumably Mobil 1.
I got great gas mileage with the 0w-30--noticably better than M1 5w-30, but my Acura RSX burned twice as much of it. Go ahead and try M1 0w-30. Your car may not burn it at all. Not all cars do.
Actually, I've been using it. Got 12 quarts of Mobil 1 TS 0w-30 a while back for real cheap. Then I started worrying that it'll shear down quickly in my Miata, with the way I drive.