Just hit 35.19 MPG last week. Never thought I'd do that well. Will I ever get 40? Unlikely but we'll see what I can do . My driving on the 35.19 didn't seem too out of the ordinary and i'm sure weather is helping out
I would say to continue testing more driving methods, and never forget some aero mods.
I went from 32-34mpg (only 2 tanks) prior to joining ecomodder to 38 with driving changes only, and soon to be 45mpg tank averages. My car is rated 26mpg average.... the toyotas (camry and corolla) both are rated really low vs my real life numbers. Camry was 22 rated and I got 27 life time average (all before ecomodder).
Point your goal for 40mpg, and some day you will get it. I never though I could even touch 45mpg with a corolla... a geo maybe but not a corolla!