Re: Car Tires on a Trailer?
Here are the regulations on tires requirements per National Highway Traffic Safety Administration, Department of Transportation.
So, where exactly is does it say that you must use trailer tires and where excatly does it say it is illegal or unsafe to use anything but trailer tires on the trailer?
Sec. 571.120 Standard No. 120; Tire selection and rims for motor
vehicles other than passenger cars.
S1. Scope. This standard specifies tire and rim selection requirements and rim marking requirements.
S2. Purpose. The purpose of this standard is to provide safe operational performance by ensuring that vehicles to which it applies are equipped with tires of adequate size and load rating and with rims of appropriate size and type designation.
S3. Application.
This standard applies to multipurpose passenger vehicles, trucks, buses, trailers, and motor cycles, to rims for use on those vehicles, and to non-pneumatic spare tire assemblies for use on those vehicles.
S4. Definitions. All terms defined in the Act and the rules and standards issued under its authority are used as defined therein.Rim base means the portion of a rim remaining after removal of all split or continuous rim flanges, side rings, and locking rings that can be detached from the rim.
Rim size designation means rim diameter and width.
Rim diameter means nominal diameter of the bead seat.
Rim width means nominal distance between rim flanges.
Rim type designation means the industry or manufacturer's designation for a rim by style or code.
Weather side means the surface area of the rim not covered by the
inflated tire.
S5. Requirements.
S5.1 Tire and rim selection.
S5.1.1 Except as specified in S5.1.3,
each vehicle equipped with pneumatic tires for highway service shall be equipped with tires that meet the requirements of Sec. 571.109, New pneumatic tires, or Sec. 571.119, New pneumatic tires for vehicles other than passenger cars, and rims that are listed by the manufacturer of the tires as suitable for use with those tires, in accordance with S4.4 of Sec. 571.109 or S5.1 of Sec. 571.119, as applicable, except that vehicles may be equipped with a non-pneumatic spare tire assembly that meets the requirements of Sec. 571.129, New non-pneumatic tires for passenger cars, and S8 of this standard. Vehicles equipped with such an assembly shall meet the requirements of S5.3.3, S7, and S9 of this standard.
S5.1.2 Except in the case of a vehicle which has a speed attainable in 3.2 kilometers of 80 kilometers per hour or less, the sum of the maximum load ratings of the tires fitted to an axle shall be not less than the gross axle weight rating (GAWR) of the axle system as specified on the vehicle's certification label required by 49 CFR part 567. Except in the case of a vehicle which has a speed attainable in 2 miles of 50 mph or less, the sum of the maximum load ratings of the tires fitted to an axle shall be not less than the gross axle weight rating (GAWR) of the axle system as specified on the vehicle's certification label required by 49 CFR part 567. If the certification label shows more than one GAWR for the axle system, the sum shall be not less than the GAWR corresponding to the size designation of the tires fitted to the axle. If the size designation of the tires fitted to the axle does not appear on the certification label, the sum shall be not less than the lowest GAWR appearing on the label.
When a tire subject to FMVSS No. 109 is installed on a multipurpose passenger vehicle, truck, bus, or trailer, the tire's load rating shall be reduced by dividing by 1.10 before calculating the sum (i.e., the sum of the load ratings of the tires on each axle, when the tires' load carrying capacity at the recommended tire cold inflation pressure is reduced by dividing by 1.10, must be appropriate for the GAWR).
