All I can say is keep trying. I was on that quest and managed 38-39mpg at least 3 times in my Matrix before I finally did 40.7 (48.8 UK) MPG out of my tank. Suprisingly the fuel light had just came on so I could've driven much longer.
Draigflag, thank you for your opinion, but would you mind toning down the America bashing? It's been getting old for a while now. Deliberately comparing US MPG to UK MPG, that doesn't help either. Also note that you used the term "old American engineering" for a Japanese car. And that the 635d is only rated at 41mpg (UK) which is 34mpg (US).
To add something to the discussion, those old Scions get great mileage and are lots of fun to drive. I'm hoping I will get to buy my mom's xA off her when I convince her to impulse-buy a Scion iQ. The best she's done with it was 40.6mpg (US).
That's OK BDC, I'm used to it. I don't know the ratings of the vehicle that Draig is speaking of, but it is of no consequence. I am not purporting that my Scion is one of the higher rated vehicles, but more so that I am coaxing 20-25% higher mileage from the vehicle than it is rated. I would be doing the same if I were driving a big truck rated at 13 mpg and getting 18 mpg.
Draig sees the need to top other people instead of just sharing his experiences. That's his right, if he wishes. People will see him for who he is and that will keep him from getting the full enjoyment of this forum.
Dont get carried away chaps. Its far too easy to jump to stereotyping on forums. I always invite people to my place to meet me before they cast judgement on my opinions. I appreciate Americans dont take critisizm too well though, they have stronger egos than us laid back Europeans :-) Did I do it again? ;-)