Greetings, all!
Over the last few days I've been watching the conversations re: tire
pressures, loads, failures, etc. Apparently, this is the topic du jour in
not just this forum, but also on one of the RV newsgroups,
rec.outdoors.rv-travel. A number of the participants on this mailing
list may also have been following the oftimes less than hospitable
exchanges over there concerning this topic, especially between a
couple of the more opinionated participants.
There appears to be not so much confusion as interpretative
disagreements about what tire manufacturers state in their inflation
tables, and what is embossed on the sidewalls of tires. Without
getting into some the technical minutiae of the discussion (and
believe me, the discussion has been valuable from a technical
standpoint) I'd like to share a couple of things that might be
germane to it.
Last Thursday afternoon, the engineering manager here in the
Towables Division (Fleetwood Enterprises, the big SOB
manufacturer) handed me a copy of a seminar guide from an
organization called "A Weigh We Go". (Please forgive if most of
you know about this organization already). They travel around the
country doing seminars on proper weighing of RVs and the
relationships between tires, inflation pressures, speed,
temperature, etc. They carry a number of wheel scales and for a
relatively reasonable fee, will weigh coaches, do a computerized
weight analysis and assist an owner in arriving at an understanding
of how tires are affected by weight and speed. This organization is
sponsored by many well-known RV manufacturers, tire
manufacturers, RV and automotive specialty suppliers, etc.
(Fleetwood neither sponsors or endorses them. Not because they
don't do good and accurate work, just because it's company policy
not to sponsor such things.)
The organization has a Web site:
http://aweighwego.org
or you can contact them at:
A Weigh We Go
211 Mae McKee Rd.
Chuckey, TN 37611
(423) 257-7985
John Anderson
I've checked it out, and have also read their seminar materials. The
Web site doesn't really tell their whole story. But the service they
provide might be one of those things that could be scheduled or
included in a GMC rally of some sort. I'm sure they would be
approachable by whomever it is that puts these rallies together. In
my thinking, a vendor or provider of such a service as this would
have to be at least as valuable as someone selling used parts or
the latest wheel polish. I'm impressed by the level of knowledge,
skill, and persistence of this (GMC) group, and in the quest for
making our coaches the best they can be, second only to making
ourselves the most capable and knowledgable RV (and personal
motoring coach) owners on the roads. "A Weigh We Go" might just
prove to be one of those fixtures at rallies that gets invited back
time after time. Just a thought. Do with as you see fit.
Additionally, Tom (our engineering manager) this morning handed
me the Tire and Rim Association Year Book (1996). Although a
couple of years old, pertinent data is still timely and applicable.
Although many of you probably have the pages from this manual
pasted to your sun visors, I've taken it upon myself to scan and
place on my Web page a couple of important tables to at least give
a flavor of the material in this book -- one the load and inflation table
for light truck metric tires for trucks, busses, etc. mounted on 5
degree drop center rims, and the load limits table for various
speeds. Both of theses tables come out of the Truck-Bus section,
not the Passenger Car section.
Use the information as you will to further your understanding of the
relationships involved. I'll not offer any interpretative comment,
except that I believe (and concur with our engineering manager)
that the expression "Tire Load Limits at Various Cold Inflation
Pressures" means that to carry the number of pounds indicated on
the table, you have to inflate the tire to the indicated psi to carry
those pounds within the speed range of the tire. Your belief system
may be different.
If you want to download the tables (they are in .PDF format,
readable and printable with Acrobat Reader) go to:
http://www.pe.net/~tmaki/
Click on "The Library", then on "The Bottom Drawer". The files are
listed under the "GMC Topics and Resources".
May this small candle be of more value as light than heat.
Later!
Toby Maki
73 Glacier 230
Redlands, CA
Over the last few days I've been watching the conversations re: tire
pressures, loads, failures, etc. Apparently, this is the topic du jour in
not just this forum, but also on one of the RV newsgroups,
rec.outdoors.rv-travel. A number of the participants on this mailing
list may also have been following the oftimes less than hospitable
exchanges over there concerning this topic, especially between a
couple of the more opinionated participants.
There appears to be not so much confusion as interpretative
disagreements about what tire manufacturers state in their inflation
tables, and what is embossed on the sidewalls of tires. Without
getting into some the technical minutiae of the discussion (and
believe me, the discussion has been valuable from a technical
standpoint) I'd like to share a couple of things that might be
germane to it.
Last Thursday afternoon, the engineering manager here in the
Towables Division (Fleetwood Enterprises, the big SOB
manufacturer) handed me a copy of a seminar guide from an
organization called "A Weigh We Go". (Please forgive if most of
you know about this organization already). They travel around the
country doing seminars on proper weighing of RVs and the
relationships between tires, inflation pressures, speed,
temperature, etc. They carry a number of wheel scales and for a
relatively reasonable fee, will weigh coaches, do a computerized
weight analysis and assist an owner in arriving at an understanding
of how tires are affected by weight and speed. This organization is
sponsored by many well-known RV manufacturers, tire
manufacturers, RV and automotive specialty suppliers, etc.
(Fleetwood neither sponsors or endorses them. Not because they
don't do good and accurate work, just because it's company policy
not to sponsor such things.)
The organization has a Web site:
http://aweighwego.org
or you can contact them at:
A Weigh We Go
211 Mae McKee Rd.
Chuckey, TN 37611
(423) 257-7985
John Anderson
I've checked it out, and have also read their seminar materials. The
Web site doesn't really tell their whole story. But the service they
provide might be one of those things that could be scheduled or
included in a GMC rally of some sort. I'm sure they would be
approachable by whomever it is that puts these rallies together. In
my thinking, a vendor or provider of such a service as this would
have to be at least as valuable as someone selling used parts or
the latest wheel polish. I'm impressed by the level of knowledge,
skill, and persistence of this (GMC) group, and in the quest for
making our coaches the best they can be, second only to making
ourselves the most capable and knowledgable RV (and personal
motoring coach) owners on the roads. "A Weigh We Go" might just
prove to be one of those fixtures at rallies that gets invited back
time after time. Just a thought. Do with as you see fit.
Additionally, Tom (our engineering manager) this morning handed
me the Tire and Rim Association Year Book (1996). Although a
couple of years old, pertinent data is still timely and applicable.
Although many of you probably have the pages from this manual
pasted to your sun visors, I've taken it upon myself to scan and
place on my Web page a couple of important tables to at least give
a flavor of the material in this book -- one the load and inflation table
for light truck metric tires for trucks, busses, etc. mounted on 5
degree drop center rims, and the load limits table for various
speeds. Both of theses tables come out of the Truck-Bus section,
not the Passenger Car section.
Use the information as you will to further your understanding of the
relationships involved. I'll not offer any interpretative comment,
except that I believe (and concur with our engineering manager)
that the expression "Tire Load Limits at Various Cold Inflation
Pressures" means that to carry the number of pounds indicated on
the table, you have to inflate the tire to the indicated psi to carry
those pounds within the speed range of the tire. Your belief system
may be different.
If you want to download the tables (they are in .PDF format,
readable and printable with Acrobat Reader) go to:
http://www.pe.net/~tmaki/
Click on "The Library", then on "The Bottom Drawer". The files are
listed under the "GMC Topics and Resources".
May this small candle be of more value as light than heat.
Later!
Toby Maki
73 Glacier 230
Redlands, CA
