Go Back   iRV2 Forums > MOTORHOME FORUMS > Class A Motorhome Discussions
Click Here to Login
Join iRV2 Today

Mission Statement: Supporting thoughtful exchange of knowledge, values and experience among RV enthusiasts.
Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on iRV2
 
Thread Tools Search this Thread Display Modes
 
Old 09-10-2012, 08:53 AM   #1
Senior Member
 
PirateCamper's Avatar
 
Join Date: Aug 2012
Location: Swansea, South Carolina
Posts: 159
Tire pressure

What tire pressure do I need to run? Tires say max is 110 pounds cold. Firestone guy said I had to tell him what to put in. Can't find it anywhere and the seller had it done at Camper World. Coach in the sig...

Thanks in advance.
__________________

__________________
1988 Coachmen 32 Ft. Sportscoach Pathfinder DL S
Class A gas, Chevy P37 Chassis 7.4L Engine
Retired Army, Swansea, South Carolina
PirateCamper is offline   Reply With Quote
Join the #1 RV Forum Today - It's Totally Free!

iRV2.com RV Community - Are you about to start a new improvement on your RV or need some help with some maintenance? Do you need advice on what products to buy? Or maybe you can give others some advice? No matter where you fit in you'll find that iRV2 is a great community to join. Best of all it's totally FREE!

You are currently viewing our boards as a guest so you have limited access to our community. Please take the time to register and you will gain a lot of great new features including; the ability to participate in discussions, network with other RV owners, see fewer ads, upload photographs, create an RV blog, send private messages and so much, much more!

Old 09-10-2012, 09:11 AM   #2
Moderator Emeritus
 
Gary RVRoamer's Avatar


 
Join Date: Jan 2000
Location: Silver Springs, FL. USA
Posts: 18,085
What size tire and what is the weight on each axle?

The 110 psi max is almost surely too much for comfort, but it is a safe choice if you can't come up with any better data.
__________________

__________________
Gary Brinck
Former owner of 2004 American Tradition
Home is in the Ocala Nat'l Forest near Ocala, FL
Summers in Black Mountain, NC
Gary RVRoamer is offline   Reply With Quote
Old 09-10-2012, 09:19 AM   #3
Senior Member
 
W4MBG's Avatar
 
Winnebago Owners Club
Ford Super Duty Owner
Join Date: Nov 2010
Location: Williamsburg, VA
Posts: 650
there should be a sticker from chevy that shows the correct tire pressure for the max weight of the chassis. better choice is get the rv weighed and go by the tire manufacturers chart.
__________________
1999 Winnebago Minnie 29', Ford V10, Close to stock.
W4MBG is offline   Reply With Quote
Old 09-10-2012, 09:26 AM   #4
Senior Member
 
JohnBoyToo's Avatar


 
Monaco Owners Club
Join Date: May 2012
Location: DFW, Tex-US
Posts: 4,843
on edit - good points put in while I was typing this
what tire brand and size, etc... ?

IMHO -
110 will get the best mpg and will give you the max carrying capacity rating of each tire.
but, will also give you the hardest ride...

put the most psi in your tires where you can still stand the ride

suggest you start at 110,
then when you have time and the rv is loaded and fueled up as if camping...
go by a cat scale and get your axle weights... then you know the max weight each tire has to carry...

look up the brand of tire you have on the mfg's web site to see if there is a chart that states what weight each level of psi will carry and build in some cushion...
i.e. sample charts may say 3300 lbs @ 80 psi and 3200 lbs @ 70 psi.... etc...

barring that chart - do a google search for the chalk test to set your psi...

in simple terms, you run chalk across the tread, drive forward on flat surface and if the chalk wears more in the center than edges, drop some psi, if wears more on the edges than center, add some psi.... this will give you the widest contact patch for YOUR rv with YOUR tires with YOUR load...
(of course make sure the adjusted psi is within the safety margin for load carrying capacity)

good luck !
__________________
'11 Monaco Diplomat 43DFT RR10R pushed by a '14 Jeep Wrangler JKU. History.. 5'ers: 13 Redwood 38gk, 11 MVP Destiny, Open Range TT, popups, vans, tents...
JohnBoyToo is offline   Reply With Quote
Old 09-10-2012, 10:54 AM   #5
Senior Member
 
PirateCamper's Avatar
 
Join Date: Aug 2012
Location: Swansea, South Carolina
Posts: 159
Thanks everyone! I'll check into this when I get home. This is the help I needed as the tires are only two years old, and I want to get the most out of them! Drive safe!
__________________
1988 Coachmen 32 Ft. Sportscoach Pathfinder DL S
Class A gas, Chevy P37 Chassis 7.4L Engine
Retired Army, Swansea, South Carolina
PirateCamper is offline   Reply With Quote
Old 09-10-2012, 11:07 AM   #6
Senior Member
 
monkey's Avatar
 
Join Date: Sep 2011
Location: Arkansas
Posts: 2,250
Quote:
Originally Posted by PirateCamper View Post
Thanks everyone! I'll check into this when I get home. This is the help I needed as the tires are only two years old, and I want to get the most out of them! Drive safe!
Good info above,, being an owner of a P30/32 chassis, once you get the pressures in the ball park for the weight, P30's are pretty picky on tire pressures compared to handling.. Up or down a couple/few lbs makes a pretty big difference in handling... Max pressure on my mh made it wander pretty bad. After reading here, I lowered the pressures a few lbs front and rear (After Weighing) and it made a world of difference in handling.
I might add make sure those older wheels can handle the higher pressures of these newer tires....
__________________
Monkey, pilot of a Great Dane hauler,
2015 Silverado 2500 Duramax/Alison 4x4 CrewCab 2016 Cougar 28SGS
1ST CAV
monkey is offline   Reply With Quote
Old 09-10-2012, 02:48 PM   #7
Senior Member
 
PirateCamper's Avatar
 
Join Date: Aug 2012
Location: Swansea, South Carolina
Posts: 159
Thank you sir!
__________________
1988 Coachmen 32 Ft. Sportscoach Pathfinder DL S
Class A gas, Chevy P37 Chassis 7.4L Engine
Retired Army, Swansea, South Carolina
PirateCamper is offline   Reply With Quote
Old 09-10-2012, 03:04 PM   #8
Senior Member
 
Mr_D's Avatar
 
Solo Rvers Club
iRV2 No Limits Club
Join Date: May 2011
Location: Vancouver, WA
Posts: 28,497
ON most RV tires the pressure on the sidewall is NOT the maximum,it is the MINIMUM for the max rating of the tire.

[QUOTE]The pressure on the sidewall of a Michelin RV tire and many others is not the "Maximum" the tire should ever have (unlike car tires) it is the minimum to support the maximum rated carrying capacity of the tire.

From the Michelin RV Tire Guide:
Quote:
"If you look at the tire's sidewall, you'll see the maximum load capacity allowed for the size tire and load rating, and the minimum cold air inflation needed to carry the maximum load."
From page 6 of the GoodYear RV Tire and Care Guide:
Quote:
"How much air is enough?
The proper air inflation for your tires depends on how much your fully loaded RV or trailer weighs. Look at the sidewall of your RV tire and you’ll see the maximum load capacity for the tire size and load rating, as well as the minimum cold air inflation, needed to carry that maximum load."
From Cooper:
Quote:
Tire Service Life

Cooper recommends that all tires, including full-size spares, that are 10 or more years from their date of manufacture, be replaced with new tires.

Tire service life is not determined by chronological age. The useful life of a tire is a function of service and storage conditions. For each individual tire, this service life is determined by many elements such as temperature, storage conditions, and conditions of use (e.g., load, speed, inflation pressure, impacts and road hazard damage) to which a tire is subjected throughout its life. Since service and storage conditions vary widely, accurately predicting the service life of any specific tire based on calendar age is not possible.

Cooper Tire is not aware of scientific or technical data that establishes or identifies a specific minimum or maximum service life for passenger and light truck tires. However, Cooper recognizes a consumer benefit from a more uniform, global industry-wide approach to the tire service life issue. Accordingly, Cooper recommends that all tires, including full-size spares, that are 10 or more years from their date of manufacture, be replaced with new tires. Tires 10 or more years old should be replaced even if the tires appear to be undamaged and have not reached their tread wear limits. Most tires will need replacement before 10 years due to service conditions. This may be necessary even if the tire has not yet reached its tread wear limits.

Under no circumstances should a "maximum" service life recommendation for a tire be considered as an "expected" service life. Tires must be removed from service for several reasons, including tread worn down to minimum depth, signs of damage (cuts, cracks, bulges, impact damage, vibration, etc.) or signs of abuse (underinflation, overloading, improper repair, etc.).
From TOYO:
Quote:

Inflation Pressure Safety Margin
Toyo Tire does not recommend an “inflate-to-the-load” policy for RV tires. Tires that are inflated to accommodate the vehicle’s actual loads do not have any inflation safety margin. Consequently, even a minor loss of air pressure will cause the tires to be under-inflated and overloaded. Toyo Tire’s policy is to observe (as a minimum) the tire pressure established by the vehicle manufacturer as indicated on the tire information placard. There are multiple reasons why a safety margin
(by inflation) makes sense:
• All tires lose about 1-1.5 PSI per month due to natural permeation of the tire’s internal air pressure through the tire’s rubber membrane.
• In the event of slow air leaks from punctures, an inflation “reserve” may allow detection and repair of the leak prior to reaching a dangerously low inflation level.
• A safety margin is prudent for users who are apathetic regarding tire inflation maintenance.
But then they go ahead and publish a weight/pressure chart allowing lower pressure for RV's!!

From the August 2010 Motorhome Magazine "Tread Carefully" tire article:
Quote:
The maximum load capacity allowed for the size tire and load rating and the minimum cold air inflation needed to carry that maximum load are located on the tire’s sidewall.
__________________
2009 45' Magna 630 w/Cummins ISX 650 HP/1950 Lbs Ft
Charter Good Sam Lifetime Member, FMCA, SKP
RV'ing since 1957, NRA Benefactor Life, towing '14 CR-V
Mr_D is online now   Reply With Quote
Old 09-10-2012, 09:18 PM   #9
Senior Member
 
PirateCamper's Avatar
 
Join Date: Aug 2012
Location: Swansea, South Carolina
Posts: 159
Thank you so very much for all the research. I'm indebted to you mate!
__________________
1988 Coachmen 32 Ft. Sportscoach Pathfinder DL S
Class A gas, Chevy P37 Chassis 7.4L Engine
Retired Army, Swansea, South Carolina
PirateCamper is offline   Reply With Quote
Old 09-10-2012, 09:59 PM   #10
Senior Member
 
PirateCamper's Avatar
 
Join Date: Aug 2012
Location: Swansea, South Carolina
Posts: 159
My tires

I have Advance 8R19.5 tires. They are two years old and have less than 1300 miles on them.

I see online that they are made in CHINA

Not real happy about that. I don't trust anything made there.
__________________

__________________
1988 Coachmen 32 Ft. Sportscoach Pathfinder DL S
Class A gas, Chevy P37 Chassis 7.4L Engine
Retired Army, Swansea, South Carolina
PirateCamper is offline   Reply With Quote
Reply



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


» Virginia Campgrounds

Reviews provided by


Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 12:23 AM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.