Date:         Thu, 24 Apr 2003 17:45:44 -0700
Reply-To:     Todd Last <rubatoguy@MINDSPRING.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Todd Last <rubatoguy@MINDSPRING.COM>
Subject:      Re: Max Load Rating Calculation
Comments: To: mark drillock <drillock@EARTHLINK.NET>
Content-Type: text/plain; charset=us-ascii

The load rating (C D E) specifies Maximum inflation pressure and Maximum load. There is no industry standard for 'ply rating' so while you may see it - no enforced standard exists.

Its pretty easy to find the table that lists Load range and max. inflation pressure - however, it is near impossible to find a table of maximum load for a given load range.

I believe this is because load range is somewhat archaic and had been superceeded by the maximum load and presusre that is stamped elsewhere on the tire.

Todd
'88 Westy


-------Original Message-------
From: mark drillock <drillock@EARTHLINK.NET>
Sent: 04/24/03 11:53 AM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: Max Load Rating Calculation

>
> The Load Range 'letter' seems to have as much or more to do with the MAX
Pressure than with a MAX weight that can be carried.
Here are the pressures I have observed to always accompany a given
letter for passenger vehicle tires.
After all these years of this topic I would think we would know
everything there is to know but it seems we don't.

B- 35 psi
C- 50 psi
D- 65 psi
E- 80 psi

Mark

TJ Hannink wrote:
>
> > How do the 93-102 load rating numbers, shown below,
> > correspond to the A,B,C,D,E load ranges?????
>
> From:
> <http://www.tiresafety.com/size_class/size_nav4b.htm#def>
>
> Ply Rating/Load Range
> While there is no industry-wide definition of ply
> rating, truck tires are frequently marked with ply
> rating and equivalent Load Range. These markings are
> used to identify the load and inflation limits of that
> particular tire, when used in a specific type of
> service. The table shows the conversion of tire
> markings.
>
>  PLY   LOAD
> RATING RANGE
>   2      A
>   4      B
>   6      C
>   8      D
>  10      E
>  12      F
>  14      G
>  16      H
>  18      J
>  20      L
>  22      M
>  24      N
>
> All "C" (or "D") rated tires don't necessarily have
> the same load rating. Michelin shows 7 "C" rated LTX
> M/S tires in various sizes, each with a different load
> rating (from 93 to 113).
> <http://www.michelinman.com/assets/pdfs/doc_ltxms.pdf>
>
> Looks to me like the alpha load range designations
> have more to do with sidewall ratings than the actual
> numerical load rating of the tire.
>
>
>