At 02:22 PM 4/15/2010, Scott Chapman wrote:
>I have Continental Vanco2's on my 85 Westy.  I inflated the tires to
>what's on the sidewalls of the tires (60psi IIRC).  The Vanagon says
>30/40.  I think inflating less than the sidewall says will decrease tire
>life substantially?  It rides like a tank at this point but I can live
>with that for a while until I find a solution and $$.

<here we go again... ;-) >

The number on the side of the tire is the maximum cold pressure
allowed for that particular tire.  That's the *only* significance it has.

The number on the vehicle is the vehicle manufacturer's best judgment
as to what inflation pressures will give the correct handling and
load capacity to the vehicle, as well as proper tire life and decent
ride.  Commonly this is tilted a bit in favor of ride, so it's a
common practice to run 3 psi or so above the recommended
numbers.  But the front-rear balance is important.  If VW thinks you
should have ten psi more in back than in front, be prepared for
handling changes if you disagree.  Some vehicles are more sensitive
to this than others -- CU once rated the Porsche 914 unacceptable
because of its extreme sensitivity to tire pressure balance.

Re wear, underinflated tires will wear out the edges and overinflated
ones will wear out the crown.  Either way you lose.  The effect
probably isn't as bad on radial tires as on bias-ply ones.

Yours,
David