Date:         Sun, 25 Jan 2004 09:44:05 -0800
Reply-To:     TJ Hannink <tjhannink@YAHOO.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         TJ Hannink <tjhannink@YAHOO.COM>
Subject:      Re: Best Tire Pressures?
In-Reply-To:  <20040125162126.11965.qmail@web60907.mail.yahoo.com>
Content-Type: text/plain; charset=us-ascii

--- tabe johnson wrote:
> Hi All,
>
> The little label inside the door has a pressure listed for 185s and
> 205 tires. The 185 pressure is quite high, anad the 205 is lower.
>
> The tires actually on my Westy right now are 195s.... Should I choose
> a pressure somewhere between the two, or go high or what? Has any
> consensus been achieved on this issue in the past, or am I just being
> crazily optimistic here?

The tire pressures shown in the door jamb are for the
tires that originally came with the van. If your tires
match the specifications shown in the door jamb
exactly, then you can use those pressures.


Tires are load rated at a specific air pressure,
sometimes different tire manufacturers require
different pressures to obtain the same load rating on
the same tire size. The pressure numbers provided in
the door jamb directly relate to the amount of air
pressure required for that particular tire to meet the
GVWR at that wheel position. On a Vanagon, the front
axle allows for less GVWR than the rear, so the tire
pressure required to support the front load will also
be less.


I had posted this to the list back on 9/02:
There is a formula for calculating the air pressure of
a non-standard sized/load rated tire using the tire
pressure recommendations on the sticker in the door
jamb. Since Vanagons have different pressure
recommendations front and rear, you need to use the
formula twice. Also, tire pressure recommendations
aren't the same for all Vanagon models, use the info
from the sticker in your van.


It is as follows:
[Original Tires Max Load Rating] * [Sticker’s
Recommended P.S.I.] / [Original Tires Max P.S.I.] *
[New Tires Max P.S.I.] / [New Tires Max Load Rating]


The tire manufacturer should be able to provide you
with a load rating vs tire pressure chart also for
your particular tire.


<http://gerry.vanagon.com/cgi-bin/wa.exe?A2=ind0209D&L=vanagon&P=R10340>


These are the numbers that I use for my tires:
Original Tire - Load rating "C" or 1,433lbs @ 48 psi
MAX
New Tire - Load rating "96" or 1,609 lbs @ 44 psi MAX

Recommended Original Pressure, 39 psi Front, 48 psi
Rear


Calculated Pressure for my tires, 33 psi Front, 40 psi
Rear


When I called Kumho and asked them for their recommendations, they asked for the front and rear GVWR and came up with the same recommended pressures.

Good luck,

=====
TJ Hannink
Goldibox - 1987 Vanagon Camper, Wolfsburg Edition
Winter Park, Florida
http://home.earthlink.net/~tjhannink/
http://groups.yahoo.com/group/wolfsburg_campers
http://photos.yahoo.com/tjhannink [Vanagon] Album





---------------------------------
Do you Yahoo!?
Yahoo! SiteBuilder - Free web site building tool. Try it!