[Still Thinking]

But, um, aren't the vehicles that consume more fuel per mile less efficient because they are heavier? Thus, the argument could be made that the existing system is actually more accurate at assessing costs based on road wear.

[EBUCK]

I don't know where the break point would be... My '65, when it ran, got about 6 miles to the gallon and weighed in at a whopping 2900 lbs. My mom-in-laws Pontiac Grand Prix weighs in at 3200 lbs and gets 25 mgp... And I've got a Samurai that wheigs less than a ton and gets 21 mpg... It would be hard to draw a true corellation.

EBUCK