[PaleMelanesian]

I completely agree about the Scangauge. He ^ said most of what I would say, but it's the single best thing I've done for my mileage. All the driving tricks will kick up a notch or two when you have instant feedback.

Tires - I'm at 53,000 miles on my tires, inflated "well above" spec for the whole time. I need to replace them soon as they're worn down to the indicator bars. Evenly worn all the way across.

I haven't found any loss of traction either , and I have places on my commute where I test that fact daily.

You didn't mention any kind of aerodynamic changes. Look at the wheels and wheel wells, the front end, etc. You could probably close half your grille and still have plenty of cooling. If you get a Scangauge you can know this for sure.