>In the US roads are mostly maintained by taxes on gas. I would think taxing tires might be a decent replacement, but I haven't seen much conversation on the issue.
Most of the conversation seems to be around taxing mileage or putting up toll roads which IMO are both crap solutions.
Taxing mileage is, is highly regressive because less wealthy people drive tons more (they live farther out from the economic centers and more frequently justify driving farther to access goods more cheaply). However, less wealthy people do not shape public policy in the kinds of states that tend to be willing to try these things out so we'll likely wind up with mileage taxes that result in people in the expensive cities and inner ring suburbs paying the least and they will be able to justify it by pointing out that the less wealthy who live in city apartments and use public transit (which is generally how the more wealthy want the less wealthy to live) pay even less.
Taxing tires is a great idea because it's a naturally progressive tax though still loosely tied to overall use. The poors on their rock hard economy all seasons will pay less than the wealthy on their super sticky and soft summers and winters. Also tire cost scales well with weight of vehicle and the heaviest vehicles do the most damage to roads. That said, I can see a lot of bad 2nd order effects (that fuel tax is mostly immune to) if we start taxing tires so I am highly apprehensive. It would be a great time to own an alignment shop though.
IMO the best solution is to just accept that good transit infrastructure is in everyone's interest and fund roads directly with general tax revenue the same way we fund subways, municipal water/sewer, parks and almost every other piece of infrastructure. The net good of the marginal cost of use being so low that pretty much anyone can use as much as they want with no cost other than opportunity cost has immense benefits to society.