Date: Sun, 29 Aug 2010 15:53:20 -0700
Reply-To: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Subject: Re: Tire question: Sorry, but ...
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
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re
The more modern system uses numeric codes to indicate the actual load a
tire can carry, _irregardless of the size_. A 97 (1609 lb) rating can
occur on tires of different sizes.
so glad there's a nice excuse to use a nonword like 'irregardelss' !
bottom line is,
stronger/better car tires are not quite as good on Vanagons as Light Truck
or Laod Range C tires are.
Probably doing all right for the amount invested.
I like really good tires I'll have to say.
You know a tire is up to any vanagon type task when it's rated for 1,800
some lbs at 65 max tire pressure.
I think having those on helps considerably in handling stability, cross wind
resistance, and the roll easier too I'd say. Gotta do some coast-down
tests on that to get something measurable and comparable.
I just think they do everything better with a good strong LT or Load Range C
tire on them.
Worth the extra cost for good new tires.
Good used tires that are close or 'pretty right' with good meat left, are so
tempting of course.
You'll be all right, but you'll be giving up some of what turly correct new
tires can give you ..
like roughly , 20 % of so. They'll do, but the real right thing is much
better.
oh yeah ...
this trip I just did. At one point I was passing a semi going downhill, two
lanes going my direction,
one lane the other, and I hit about 75 mph passing him ( 85 Westy GL , LT
and 8PR 14 inch tires, stock steel wheels ) ...
at the same time another semi passed going the other direcion. My closing
speed with him was about 120mph at least, he's going by on the left, 5 feet
away, while I'm going by the other one on the right, at 70ish + speed. (
Hwy 97 in Oregon, south of Bend ) .
For about maybe 5 to 10 seconds, if there was a blow out in a front tire,
we'd likely be dead.
For that short period, zero margin for anything tire wise to go wrong ...
I know what the production date on the front tires is too ......
sure made me want four fairly new really solid strong tires on that mutha.
----- Original Message -----
From: "Mike S" <mikes@FLATSURFACE.COM>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Sunday, August 29, 2010 2:20 PM
Subject: Re: Tire question: Sorry, but ...
> At 01:03 PM 8/29/2010, Don Hanson wrote...
>> The ones I just got are marked "205/70 r 14 95T M+S" with a max
>> load
>>rating of 1527# and they are set up for studs, but have none in
>>them I
>>guess, from what I have found on the net, that these are likely car
>>tires,
>>not light truck like the other Hakkas I have. They do have an
>>adequate load
>>rating for the weight of my van,
>
> They don't have enough of a load rating to allow you to load your
> Vanagon to its rated capacity.
>
> I did a bit of research on this a while ago, and put together this
> summary:
>
> VW considers the Vanagon a light truck. When they originally spec'd
> tires, light truck tires were rated by ply ratings (6PR, 8PR, etc.)
> and/or letter load ranges (A, B, C, etc.). The spec'd a 185/14 6PR/load
> range C.
>
> For passenger car tires, they spec'd a reinforced tire. "Reinforced"
> (the term "Extra Load" is also used) in this context only means that
> the tire is specified to have a significantly greater load handling
> capacity than a standard passenger car tire of the same size.
>
> All of those ratings, PR, letter load range, and "reinforced" (or
> "extra load") modify the load rating of _the base tire size_. That is,
> a 6PR rated tire of one size might have a different load carrying
> ability than a 6PR rated tire of a different size. Those ratings still
> appear on tires only for backward compatibility with older
> specifications. (i.e. for someone looking for a 185R14C 6PR light truck
> tire or a 185R14 reinforced passenger car tire)
>
> The more modern system uses numeric codes to indicate the actual load a
> tire can carry, _irregardless of the size_. A 97 (1609 lb) rating can
> occur on tires of different sizes. This makes things MUCH simpler,
> especially if changing tire sizes. When using this system, the PRx,
> reinforced, etc. ratings aren't needed.
>
> Passenger car tires need to be derated 9% when used for a light truck
> application (because light trucks have a higher center of gravity, are
> expected to be loaded near capacity more often, etc.).
>
> Reference: http://www.tirerack.com/tires/tiretech/tirespecskey.jsp
>
> For use on a Vanagon, a passenger car tire must be load rated 97 (1609
> lbs). And that is exactly what VW used when they provided passenger car
> tires as original equipment on the Vanagon, toward the end of its life.
> When derated by 9%, that 1609 lbs becomes 1464 lbs. That is the closest
> match to the GAWR-rear (2866 lbs.), without going under. The next step
> down, a 96 (1565 lb.) rating, would derate to 1424 lbs., too low for
> the Vanagon's actual weight rating.
>
> If VW were spec'ing tires today, they would say use a light truck tire
> of load range 93 (1433 lbs) or greater. That exactly matches the
> GAWR-rear (maximum rear axle load) rating of 2866 lbs. Or, use a
> passenger car tire of load rating 97 or higher, which when derated
> properly, is as close as you can get without going under.
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