10K MPG Check: Not impressed

They are wider (which I still think hurts the FE more than the weight)

 

For me 50 mpg has been absolutely no problem. Over the last ~2100 miles the display reads 59.5 mpg. I calculated one tank manually and it was 58.05 mpg vs 62.5 on the display. I'm guessing my 59.5 lifetime average is closer to 56. I have noticed a difference now that temps have fallen ~15 degrees. During 90-95 degree summer days I was up to 66-69 mpg.

 

Weight is a huge factor on MPG, probably much more than the 17" wheels. I have experience with this every week when traveling 360 miles each way, round trip.

Outbound trip: the car goes moderately heavy (at least 400-450 pounds considering my weight) and I'm getting 48-49 MPG. I do drive considerably over speed limit (passport 9500xi keeps me clean and safe), my average speed is 67, which is pretty high considering that about 50% of the way have speed limits bellow my average, which is 65 or lower).

Inbound: Car goes at least 200 pounds lighter and I get 53-54 with the same conditions. The way back and forth is pretty flat, so the only thing to blame is the cargo weight.

So, just 200-250 pounds of extra cargo is resulting in a 4 MPG hit in my case.