Originally Posted by 79letour
My ism premium 5mt gets grest mileage. Right now its showing 31.5 as the average. Even with the error in the optimistic readout its really good. I'm not suggesting anyone do this- but fwiw I switched all my fluids over to Amsoil early on and have never had any complaints about mpg's. I mostly make short trips less than twenty miles in 45mph zones.
Which Amsoil are you using? I may go ahead and switch over, as my cvt gets about 8 mpg worse than my identically rated Corolla that's been running Amsoil Signature Series for over 150,000 miles, with an average change interval of about 20,000 miles.