>Ari Ollikainen wrote:
>>
>>         In response to my posting of a load index for values of 71-110,
>>         at 9:15 PM 10/26/98, David-M wrote:
>>
>> >There is also some law that says that for a passenger tire on a truck,
>> >you have to reduce the load rating by 10%. That definitely applies to
>> >the Vanagon.
>>
>>         That's interesting...whose law is it, who does it apply to, and
>>         can you provide a cite?
>>
>Go here:
>
>http://www.roadmastertire.com/cooper/discover.htm
>
>It may not be a law, just an industry standard, but I am sure there is
>good reasoning behind it.

        Fascinating chart, especially the 35psi tire pressure for the
        Cooper Discover tires, is that MAX?

        It's the industry (Tire and Rim Association) covering its behind
        (by 10%?...hardly seems worth it). Interestingly the 10% reduction
        is for the NorthAmerican P-Metric tire sizes used "in light truck
        services" and doesn't apply to the European metric (no P in front,
        as in 205/70 versus P205/70) sizes...not that it matters, since
        Cooper doesn't make the Discover in a metric.

        Once more, it all depends on the definition of "light truck services".

        Regardless, in my opinion, stinting on tires is pure foolishness.!

        BTW, there actually <GASP!> is a CANADIAN law that specifies the
        derating for non-passenger car uses of passenger car tires somewhat
        obscurely (and results in a reduction of 9% due to the calculation
        method!):

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        [http://www.tc.gc.ca/actsregs/mvsa/english/mvsr120.html]

        Motor Vehicle Safety Act

        Motor Vehicle Safety Regulations

        Standard 120

        Tire Selection and Rims for Vehicles
        Other Than Passenger Cars

        120. (1) Subject to subsection (5), the tires of every bus,
        chassis-cab, motorcycle, motor driven cycle, moped, multipurpose
        passenger vehicle, trailer, trailer converter dolly and truck shall
        meet the requirements of the Motor Vehicle Tire Safety
        Regulations.

        (2) Every motor vehicle described in subsection (1) shall be equipped
        with rims that are listed by the manufacturer of the tires as
        being suitable for use with the tires of the motor vehicle in
        accordance with subsection 1(1) or 2(1) of Schedule V to the Motor
        Vehicle Tire Safety Regulations.

        (3) The sum of the maximum load ratings of the tires fitted to an axle
        shall

        (a) be not less than the gross axle weight rating (GAWR) of the axle
        system as specified in the vehicle's statement of compliance label as
        required by section 6 of the Regulations;

        (b) where the statement of compliance label shows more than one GAWR
        for the axle system, be not less than the GAWR corresponding to the
        size designation of the tires fitted to the axle; and

        (c) where the size designation of the tires fitted to the axle does
        not appear on the statement of compliance label, be not less than
        the lowest GAWR appearing on the label.

>>>>>   (4) For the purpose of determining the sum referred to in subsection
>>>>>   (3), where a bus, chassis-cab, multipurpose passenger vehicle,
>>>>>   trailer, trailer converter dolly or truck is equipped with a passenger
>>>>>   car tire, the maximum load rating of that tire shall be
>>>>>   divided by a factor of 1.10.

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      OLTECO                    Ari Ollikainen
      P.O. BOX 3688             Networking Technology and Architecture
      Stanford, CA              Ari@OLTECO.com
      94309-3688                415.517.3519