Actual unloaded weight—(1) In general. Actual unloaded weight means the empty (or tare) weight of the truck, truck-tractor, or bus, fully equipped for service.

Trucks and truck-tractors. A truck or truck-tractor fully equipped for service includes the body (whether or not designed and adapted primarily for transporting cargo, as for example, concrete mixers); all accessories; all equipment attached to or carried on such truck or truck-tractor for use in connection with the movement of the vehicle by means of its own motor or for use in the maintenance of the vehicle; and a full complement of lubricants, fuel, and water. It does not include the driver, any equipment (not including the body) attached to or carried on the vehicle for use in handling, protecting, or preserving cargo, or any special equipment (such as an air compressor, crane, specialized oilfield machinery, etc.) mounted on the vehicle for use on construction jobs, in oilfield operations, etc.

Buses. A bus fully equipped for service includes the body; all accessories; all equipment attached to or carried on such bus for use in connection with the movement of the vehicle by means of its own motor, for use in the maintenance of the vehicle, or for the accommodation of passengers or others (such as air conditioning equipment and sanitation facilities, etc.); and a full complement of lubricants, fuel, and water. It does not include the driver.

Determination of taxable gross weight—(1) In general. The taxable gross weight of a highway motor vehicle is the sum of the actual unloaded weight of the vehicle fully equipped for service, the actual unloaded weight of any semitrailers or trailers fully equipped for service customarily used in combination with the vehicle, and the weight of the maximum load customarily carried on the vehicle and on any semitrailers or trailers customarily used in combination with the vehicle. In the case of a highway motor vehicle that is registered in at least one State that requires a declaration of gross weight to be stated as a specific amount for any purpose (including proportional or prorate registration or the payment of any other fees or taxes), the taxable gross weight of such vehicle must be no less than the highest gross weight declaration (or combined gross weight declaration in the case of a tractor-trailer or truck-trailer combination) made by the registrant in any State with respect to such vehicle. If a highway motor vehicle is registered in at least one State that requires vehicles to register on the basis of gross weight and such vehicle is not registered in any State that requires a declaration of gross weight to be stated as a specific amount by the registrant, the taxable gross weight of such vehicle must fall within the highest gross weight category of such State for which such vehicle is registered during the taxable period. Declarations of weight made in order to obtain special temporary travel permits which allow a vehicle to, (i) operate in a State in which the vehicle is not registered or prorated, (ii) operate at more than a State's maximum statutory weight limit, or (iii) operate at more than the weight that the vehicle is registered in a State, shall not be considered in determining the taxable gross weight of a vehicle.

Buses. For purposes of the tax imposed by section 4481(a), the taxable gross weight of a bus shall be the sum of the weights referred to in paragraph (b)(1) of this section except that “the weight of the maximum load customarily carried” on a bus shall be equal to 150 pounds times the number of units of seating capacity provided for passengers and driver.

Examples. The provisions of this section may be illustrated by the following examples:

A is the owner of a truck-tractor. On January 1, 1985, A registers the truck-tractor in three states—X, Y, and Z. For purposes of registering the vehicle in State X, A declares the gross operating weight of his truck-tractor to be 60,000 pounds. The declaration of the gross weight of the vehicle at 50,000 pounds places A's truck-tractor in the State X registration category of 55,000 to 62,000 pounds gross weight. Thus, the registered weight of A's vehicle in State X is 62,000 pounds. At the same time as A registers the vehicle in State X, A also proportionally registers the vehicle under the IRP in State Y. A uses the same declared gross weight of 60,000 pounds for purposes of the State Y proportional registration. Registration in State Y at this declared gross weight places A's truck-tractor in the State Y gross weight registration category of 58,000 to 68,000 pounds. Finally, A registers the truck-tractor in State Z. Registration of vehicles in State Z is based on the unladen weight of the vehicle. During the taxable period beginning on July 1, 1985, A's truck-tractor is not registered in any other state. For the taxable period beginning on July 1, 1985, A must declare a taxable gross weight of no less than 60,000 pounds for purposes of the tax imposed by section 4481(a) because that is the highest declared gross weight for state registration or other purposes. Should A declare to any State agency a higher gross operating weight with respect to the truck-tractor during the same taxable period (except for a special temporary permit), A would then be liable for additional tax as determined under paragraph (c)(3) of § 41.4481-1.

Assume the same facts as in example (1), except that on one occasion during the taxable period, A was issued a special 2-day permit to use his truck-tractor in State Y to haul a load which would give A's unit a total gross weight of 80,000 pounds. A may still declare the taxable gross weight of his unit to be no less than 60,000 pounds because special permits to haul heavier loads on a temporary basis are not considered in determining the taxable gross weight of a vehicle.

C owns and has registered in his name 2 trucks which are identical in all respects and which are used to carry the same type of load. The first vehicle is registered only in State X at a registered weight of 73,000 pounds based on a declared gross weight of 70,000 pounds. The second vehicle is registered only in State Y at a registered weight of 68,000 pounds based on a declared gross weight of 65,000 pounds. No other declarations of gross weight are made with respect to either vehicle. For purposes of the Federal heavy vehicle use tax, the taxable gross weight of the vehicle registered in State X may be declared at no less than 70,000 pounds and the taxable gross weight of the vehicle registered in State Y may be declared at no less than 65,000 pounds even though the vehicles are identical.