mr. frugal-mpg:

I am in the Eugene area myself, and yet to find a honest mechanic besides the dealer.

 

A tonneau cover may help with your mileage.

 

It appears you've got the right tires and driving habits. If you're looking for a cheap easy way a lot of us have had good luck upping economy with the quadzilla xzt towing chip. I got 1+ mpg out of mine based on hand calc. I bought one used for $200.

I never saw any improvements on economy with intake and exhaust upgrades. Fuels additives are expensive and will not improve your economy enough, if any at all, to recoup the extra costs. Be very skeptical of those claims. Acetone is a solvent. Don't put that crap in your fuel tank.

 

ya acetone is a solvent but its mixed at such a low dose it wont do anything,most additives have solvents to clean and they may be worse than acetone,pure 100%acetone is 140 octane which will help with combusion,like i stated i think it may work on gas stuff