[Fr3AkAzOiD]

Well I have been running it since winter, that and going from 38 - 42 psi in my tires were were pretty much the only "mods" I made over the winter.

Since then I have beaten my personal best from last summer for individual trips several times but that could just be from improved technique.

I think the Mobile 1 0W-30 Advanced Fuel Economy helps most when...
a. your car is not up to normal running temp yet.
b. your in cold weather.

From what I can gather the oil is designed to not be overly thick when cold and thus reduces resistance as it acts like normal not synthetic oil does when it's up to normal operating temps instead of acting like maple syrup when you just start up your car that has been sitting outside in 15 degree weather overnight.

Now did I see a change....not really.
I'm getting better milage then I ever have but I did stop hypermiling 2 winters ago so I can't compare winter driving year to year.

But I'll be honest, even if it bumped me up 0.5 mpg on average it would be hard for me to tell cause even with driving the same route every day traffic is vastly different and one tank I may get 52 mpg and the next I may only get 48 mpg and 0.5 mpg gains would easily get lost in there.

However before this I never changed my own oil and just took it to the local mechanic and I actually save $5 - $10 every time I change my own oil and I know what oil and filter I am putting in my car so I am happy.