Re: First Tank MPG (my story), would like to hear yours
I have kept mileage calculations for every tankful in my vehicles for over 35 years. The effect of a new engine is highly overrated when I look at those records; but maybe there is a small effect in the first 1000 miles or so.
Far more significant effects are air temperature, wind direction, whether the A/C and other high power draw accessories are running, rain or snow on the road, tire inflation, flat vs. hilly terrain, trailering, etc. Any one tankful can be off the normal range for so many reasons. I'd say continue your break-in and see how it looks after four or five tankfuls.
One thing I have seen from my own calcs though: driving faster on the highway does not have as much real-world effect on my mileage as some pundits say. They never seem to factor in that when I am going a faster speed, or course I am using more gas, but I'm also going a further distance in the same time, plus the engine may be working in a sweeter spot of its power curve. etc. My Jeeps have usually had their best full-tank highway mileage at about 70mph, rather than 50.
2011 GC OL, Natural Green/Frost, QL, ORGII, 430N, Pano, GY WSA