Del Rawlins

On 08 Dec 2003 03:44 PM, Irish Redneck posted the following:
> On Sun, 7 Dec 2003 17:49:04 -0800, CRWLR <CRWLRJEFF@YAHOO.COM> wrote:
>
>> NEVER load a tire to the specs shown on the sidewall. There is no way
>> you
>
> NEVER load a tire to the specs shown on the sidewall? why are these
> specs there?

The point is, even if the sidewall spec happens to be the amount of air
you are using, it is not how you get there. The correct amount of air
pressure in the tire is based upon the axle loading divided by the
number of tires per axle, and correct size of the contact patch. You
get there by either using the vehicle manufacturer's spec (i.e. door
jamb tag), or by one of the several emperical methods for determining
the air pressure, like the chalk method or the card trick.

The sidewall spec tells you what the maximum load allowed on that
particular tire is, and it is determined solely by the tire's internal
construction. Practically speaking, if you need to put in a higher
pressure than the sidewall spec to get the needed contact patch size,
then you are overloading that tire and need to either lighten the load
or upgrade to a heavier duty tire. Conversely, if you are at the max
pressure listed on the sidewall and are getting too much tread contact
and sidewall bulge, then you also need to lighten up or install heavier
rated tires.

Another point to remember when you upgrade from stock tires to heavier
duty light truck rated tires like many of us do with our Jeeps (the
stockers are "P" rated aka passenger car tires), that just because the
tire can take the additional load, it probably isn't a good idea to
exceed your rigs GVWR since other factors come into play like suspension,
wheelbase, etc. The tires are just no longer the weak point. The main
benefit of switching to LT rated tires is the increased durability,
which actually is just a by-product of the additional internal structure
needed to carry the additional rated load, even if you can't use that
capacity for other reasons.

Think of it like installing heavy duty drivetrain parts, where you are
just shifting the weak point around to different components until you
reach a point where it doesn't break anymore.

----------------------------------------------------------
Del "Mighta been an engineer but for the Calculus" Rawlins
del@_kills_spammers_rawlinsbrothers.org
Remove _kills_spammers_ to reply via email.
Unofficial Bearhawk FAQ website:
http://www.rawlinsbrothers.org/bhfaq/

Matt Macchiarolo

In article <vta0qhq97vc470@corp.supernews.com>, "CRWLR" <beerman@yahoo.com>
writes:

>In the context of the original poster, never fill any tire to the numbers
>printed on the sidewall.

unless the doorjamb says to, I had a van that called for a tire pressure that
happened to be the max on the tire sidewall.
* * *
Matt Macchiarolo
www.townpeddler.com
www.wolverine4wd.org
http://wolverine4wd.org/rigs/macchiarolo_ml.html

Matt Macchiarolo

In article <vta0qhq97vc470@corp.supernews.com>, "CRWLR" <beerman@yahoo.com>
writes:

>In the context of the original poster, never fill any tire to the numbers
>printed on the sidewall.

unless the doorjamb says to, I had a van that called for a tire pressure that
happened to be the max on the tire sidewall.
* * *
Matt Macchiarolo
www.townpeddler.com
www.wolverine4wd.org
http://wolverine4wd.org/rigs/macchiarolo_ml.html

Matt Macchiarolo

In article <vta0qhq97vc470@corp.supernews.com>, "CRWLR" <beerman@yahoo.com>
writes:

>In the context of the original poster, never fill any tire to the numbers
>printed on the sidewall.

unless the doorjamb says to, I had a van that called for a tire pressure that
happened to be the max on the tire sidewall.
* * *
Matt Macchiarolo
www.townpeddler.com
www.wolverine4wd.org
http://wolverine4wd.org/rigs/macchiarolo_ml.html

TJim

The max air pressure on the side of the tire is just that: MAX. Short for
Maximum, meaning "the most this tire will tolerate". The proper pressure
for any tire is the pressure that will give you a full footprint with the
tire on a particular vehicle, not the max. The proper pressure on that tire
on a wrangler is going to be different than for the same tire on a lighter
or a heavier vehicle. Normal driving puts stresses on a tire (bumps and
heat mostly) that will raise the tire pressure, if even momentarily.
If you fill a tire to the max pressure, you are begging for a catastrophic
blow-out. In addition, you are reducing your tread contact patch and
degrading the quality of your ride. There is no reason to do this. If
you're looking for better gas mileage, get a Honda... and fill the tires to
their proper pressure.

--
Jim

"Irish Redneck" <seeayeemm@hotmail.com> wrote in message
news:oprzv1numdy2qpcc@netnews.insightbb.com...
> On Sun, 7 Dec 2003 17:49:04 -0800, CRWLR <CRWLRJEFF@YAHOO.COM> wrote:
>
> > NEVER load a tire to the specs shown on the sidewall. There is no way
you
>
> NEVER load a tire to the specs shown on the sidewall? why are these specs
> there?
>
>
> > will enjoy the ride at 80 psi because you will have nowhere near the
> > weight
> > limits that they suggest as the max capacity of the tire.
>
> how do you know this?
>
> > Take a look at ANY tire and it will have similar information on it. This
> > information has nothing to do with real life applications. It is the
>
> nothing to do with real life applications? i still don't understand.
> maybe your real life and REAL life are different!
>
> > MAXIMUM
> > weight the tire can carry, and the max pressure yo can put in at that
> > weight.
>
> long-winded way of saying 1000psi @ 10,000lbs?
>
>
> > The rest of the time, put in somewhere between 25 and 30 psi, and leave
> > it
> > at that.
>
> have a bad day at work? this last line is all that was necessary to
convey
> your opinion!
>

TJim

The max air pressure on the side of the tire is just that: MAX. Short for
Maximum, meaning "the most this tire will tolerate". The proper pressure
for any tire is the pressure that will give you a full footprint with the
tire on a particular vehicle, not the max. The proper pressure on that tire
on a wrangler is going to be different than for the same tire on a lighter
or a heavier vehicle. Normal driving puts stresses on a tire (bumps and
heat mostly) that will raise the tire pressure, if even momentarily.
If you fill a tire to the max pressure, you are begging for a catastrophic
blow-out. In addition, you are reducing your tread contact patch and
degrading the quality of your ride. There is no reason to do this. If
you're looking for better gas mileage, get a Honda... and fill the tires to
their proper pressure.

--
Jim

"Irish Redneck" <seeayeemm@hotmail.com> wrote in message
news:oprzv1numdy2qpcc@netnews.insightbb.com...
> On Sun, 7 Dec 2003 17:49:04 -0800, CRWLR <CRWLRJEFF@YAHOO.COM> wrote:
>
> > NEVER load a tire to the specs shown on the sidewall. There is no way
you
>
> NEVER load a tire to the specs shown on the sidewall? why are these specs
> there?
>
>
> > will enjoy the ride at 80 psi because you will have nowhere near the
> > weight
> > limits that they suggest as the max capacity of the tire.
>
> how do you know this?
>
> > Take a look at ANY tire and it will have similar information on it. This
> > information has nothing to do with real life applications. It is the
>
> nothing to do with real life applications? i still don't understand.
> maybe your real life and REAL life are different!
>
> > MAXIMUM
> > weight the tire can carry, and the max pressure yo can put in at that
> > weight.
>
> long-winded way of saying 1000psi @ 10,000lbs?
>
>
> > The rest of the time, put in somewhere between 25 and 30 psi, and leave
> > it
> > at that.
>
> have a bad day at work? this last line is all that was necessary to
convey
> your opinion!
>

TJim

The max air pressure on the side of the tire is just that: MAX. Short for
Maximum, meaning "the most this tire will tolerate". The proper pressure
for any tire is the pressure that will give you a full footprint with the
tire on a particular vehicle, not the max. The proper pressure on that tire
on a wrangler is going to be different than for the same tire on a lighter
or a heavier vehicle. Normal driving puts stresses on a tire (bumps and
heat mostly) that will raise the tire pressure, if even momentarily.
If you fill a tire to the max pressure, you are begging for a catastrophic
blow-out. In addition, you are reducing your tread contact patch and
degrading the quality of your ride. There is no reason to do this. If
you're looking for better gas mileage, get a Honda... and fill the tires to
their proper pressure.

--
Jim

"Irish Redneck" <seeayeemm@hotmail.com> wrote in message
news:oprzv1numdy2qpcc@netnews.insightbb.com...
> On Sun, 7 Dec 2003 17:49:04 -0800, CRWLR <CRWLRJEFF@YAHOO.COM> wrote:
>
> > NEVER load a tire to the specs shown on the sidewall. There is no way
you
>
> NEVER load a tire to the specs shown on the sidewall? why are these specs
> there?
>
>
> > will enjoy the ride at 80 psi because you will have nowhere near the
> > weight
> > limits that they suggest as the max capacity of the tire.
>
> how do you know this?
>
> > Take a look at ANY tire and it will have similar information on it. This
> > information has nothing to do with real life applications. It is the
>
> nothing to do with real life applications? i still don't understand.
> maybe your real life and REAL life are different!
>
> > MAXIMUM
> > weight the tire can carry, and the max pressure yo can put in at that
> > weight.
>
> long-winded way of saying 1000psi @ 10,000lbs?
>
>
> > The rest of the time, put in somewhere between 25 and 30 psi, and leave
> > it
> > at that.
>
> have a bad day at work? this last line is all that was necessary to
convey
> your opinion!
>