[ndsipa_pomu]

It's a tricky thing to implement as the road damage is typically quoted as being proportional to the fourth power of axle weight. That means that either the heaviest vehicles would become economically unviable due to the taxation (which I think should be the case) or most consumer vehicles would be too light to make a meaningful taxation contribution.

[syzarian]

A 2000 pound vehicle driven an average of 15000 miles per year does $x of damage to the roads. X is a calculable figure. Tax the vehicle to at least pay $x. If it is in the pennies then tax that amount. That a heavier vehicle does more damage just means calculating the appropriate amount to tax it.

[ndsipa_pomu]

It could work out that it costs more to implement the smaller vehicle tax than it would recover in revenue. Also, there's a major problem with logistics companies having considerable power over politicians, so I can see problems with getting them to pay for their considerable share of the road repair costs.