The report showed everything good except the viscosity.The report stated that the viscosity was equal to 15/40 instead of the 0/30 stated on the label.When I e-mailed Amsoil they said you should be happy with the report!!! as the wear #'s where great!! I complained to them that it wasn't just the extended use that attracted me to the s2k,but also the ability to run in colder climates and the claimed fuel savings.My car has 72,000 miles on it and I commute 400 miles a week. 50% in the mountains and 50% freeway driving.Within the 10,000 miles I added 5 make-up quarts for oil changes and topping off. I change filters every 5,000 miles (K&N). I have a few questions that Amsoil had a hard time answering. Why did the viscosisty increase to 15/40? Will the viscosisty increase much more? Will 15/40 be a problem when the weather drops to 27 degrees? Will the higher viscosity hurt or help the gas mileage?