> A 3/4-ton pickup vs your toyota camry is MAYBE a 2x increase in damage to the road.
Your source states that relative road damage between two vehicles is the forth power of the ratio of their weights.
The base curb weight of a Ford F-150 is in the vicinity of 4,600lbs. The base curbs weight of a Toyota Camry is in the vicinity of 3,500lbs. So the damage ratio is (46/35)^4 = ~3. The Toyota Camry used to be a small car, but it isn't anymore. The base curb weight of a Ford Fiesta is in the vicinity of 2,500lbs. So the damage ratio between a Toyota Camry and a Ford Fiesta is (35/25)^4 = ~3.8, and between a Ford F-150 and a Ford Fiesta is (46/25)^4 = ~11.5. So a Toyota Camry, being somewhat of a behemoth, should be paying on the order of 3.8x the amount of road tax as a Ford Fiesta.
Your source states that relative road damage between two vehicles is the forth power of the ratio of their weights.
The base curb weight of a Ford F-150 is in the vicinity of 4,600lbs. The base curbs weight of a Toyota Camry is in the vicinity of 3,500lbs. So the damage ratio is (46/35)^4 = ~3. The Toyota Camry used to be a small car, but it isn't anymore. The base curb weight of a Ford Fiesta is in the vicinity of 2,500lbs. So the damage ratio between a Toyota Camry and a Ford Fiesta is (35/25)^4 = ~3.8, and between a Ford F-150 and a Ford Fiesta is (46/25)^4 = ~11.5. So a Toyota Camry, being somewhat of a behemoth, should be paying on the order of 3.8x the amount of road tax as a Ford Fiesta.