[snibsnib]

Where i live, 80% of all vehicles are passenger vehicles. I'm not sure that the extra wheels on semis would make up for that difference, especially with the slow increase in size of passenger vehicles.

[Retric]

Something like 98% of ware from road vehicles is caused by semi’s vs 2% from cars and trucks.

20% * 18 = 3.6 vs 80% * 4 = 3.2, so barring some 3rd category semi’s would have more tires. They also have a lot more weight on each of those tires.

[Aurornis]

Road wear is proportional to weight.

Semi tires are hard, long-lasting compounds relative to soft consumer tires with deep treads and soft rubber.