Huston55
Thinks s/he gets paid by the post
Yes, that's a tax specifically on trucks. If a truck travels 90,000 miles per year and gets 6 mpg, that's 15,000 gallons of fuel. Then $550 is the equivalent of 4 cents per gallon.
My comment on subsidies was based on reading that road damage varies with the third or fourth power of weight per axle. An ordinary car might put 2,000 pounds on each of it's two axles. A semi, 10,000 pounds on each of its five axles. Now (10,000/2,000)^3 = 125. So each truck axle seems to do as much damage as 125 car axles. Then, the truck has 2.5 times as many axles, so I'm at 300 times the damage per vehicle.
Trucks get poorer fuel mileage. Maybe a semi burns 4 times as much fuel per mile as a car. And, not all the costs of roads are repair/replacement. The original construction costs include land acquisition and rough grading, for example.
Still 300 >>> 4. It seems that anything remotely close to equal tax per gallon must result in a "subsidy" for the trucks.
+1
And, your math is right on.