Date: Mon, 1 Aug 2005 10:33:12 -0700
Reply-To: mark drillock <drillock@EARTHLINK.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: mark drillock <drillock@EARTHLINK.NET>
Subject: Re: Tire pressure question 2
In-Reply-To: <000d01c596b4$56c1d370$0a0ba8c0@RON>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Look at the door stickers, Ron. Some years VW listed rear tire pressure
of 53 psi for one size of 14" tire and the SAME sticker lists 40 psi in
the rear for another 14" size tire. I don't think those numbers were
randomly selected. How do you explain the large disparity in recommended
pressure? I explain it by saying that VW used 55 psi max tires in the
one size and 41 psi max tires in the other size and then kept the
recommended pressure below the max. Other years they listed 48 psi for
that size instead of 53. My guess is that those years used 50 psi max
tires so the sticker reflects that.
Current 6PR/LoadC tires have 50 psi max for the most part. Do you
suggest these be inflated to 53 per the sticker when those tires are
fitted? If as you suggest VW changed the recommended pressures as "the
result of test track results, engineering data, tire manufacturer input,
dealer feedback, warranty claim data, or any of a number of factors"
then should owners of similar earlier models switch to the later
pressures? That is the kind of question we are trying to resolve.
Mark
The Bus Depot wrote:
>>Over the years the sticker data turned into a bit of a mess since
>>VW adjusted the sticker to reflect that tires that actually came
>> on the given year
>>
>>
>
>
>We can only guess at why VW changed the recommended inflation levels. I am
>not sure that it always had to do with what tires came on the vehicle, as I
>believe that there are cases where the OE tire itself was not changed but
>the sticker data was. In other cases it occurred during, or shortly after,
>significant changes to the vehicle design (such as engine size/weight). The
>changes that VW made may have been the result of test track results,
>engineering data, tire manufacturer input, dealer feedback, warranty claim
>data, or any of a number of factors. The recommended specifications for a
>vehicle are generally based on a good bit of engineering and testing, not
>just randomly determined. Similarly, when a manufacturer makes a change to
>the specifications on a subsequent year there is usually a solid reason why
>they did so; it's not just an "off the cuff" decision. The most conservative
>course of action, of course, is stay very close to the tire inflation
>specifications that Volkswagen recommended for your vehicle, rather than
>second-guessing Volkswagen's engineers based only on wild guesses as to why
>they picked the numbers that they did.
>
>- Ron Salmon
> The Bus Depot, Inc.
> www.busdepot.com
> (215) 234-VWVW
>
>_____________________________________________
>Toll-Free for Orders by PART # : 1-866-BUS-DEPOT
>
>
>
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