Go Back   iRV2 Forums > iRV2.com COMMUNITY FORUMS > iRV2.com General Discussion
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 03-04-2014, 09:50 AM   #1
Member
 
Join Date: Mar 2014
Posts: 38
Best Tire Pressure?

Hello everyone,

I just purchased a 2008 Fleetwood Fiesta LX 34n. The dealer just put 6 new 235/80R 22.5 Sumitomo tires on the coach. I was wondering what is the best tire pressure to keep these tires at. I am looking for that balance of good MPG and tire ware. Thank you for any advice.
__________________

__________________
mgjessop 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 03-04-2014, 10:20 AM   #2
Senior Member
 
al2ride's Avatar
 
Join Date: Jan 2014
Posts: 1,278
You can go with what's on the label in the coach. However, if you want to know the best PSI for your tires you'd have to weigh the coach and go with the tire manufacturer's recommended pressure based on the weight.
__________________

__________________
USAF Veteran
2014 Forest River Georgetown 351DS
2014 Jeep Wrangler Unlimited Rubicon Toad
al2ride is offline   Reply With Quote
Old 03-04-2014, 10:31 AM   #3
Moderator Emeritus
 
RickO's Avatar


 
Join Date: Jan 2007
Location: Litchfield Park, Arizona
Posts: 10,530
Hi and welcome to the forum.

Frankly, I'd be more concerned with ride comfort than tire wear. RV tires almost never wear out before they time out and need to be changed because of age. If your tires are over inflated for your weight it can make it feel like you've bought a bucket of bolts because of the harsh ride and it might even impact handling.

You can use the placard in the coach and you'll be safe so long as you're not overloaded, but the proper way is to go to a truck stop and get at least each axle weight. Then go to the tire mfgr's website and look up what your tires should be inflated to to support your particular weight.


Rick
__________________
Rick, Nancy, Peanut & Lola our Westie Dogs & Bailey the Sheltie.

2007 Itasca Ellipse 40FD
RickO is offline   Reply With Quote
Old 03-04-2014, 10:52 AM   #4
Senior Member
 
JJH3rd's Avatar


 
National RV Owners Club
Workhorse Chassis Owner
Join Date: Feb 2011
Location: Covington, GA
Posts: 505
Send a message via Skype™ to JJH3rd
The manufacturer's labels, pasted somewhere in your coach, shows the tire pressure that the manufacturer used in the design of the suspension. Inflate the tires to that pressure for the best handling/ride.

I know this from direct experience. When we first had the MH, I inflated the tires (Michelin XRV) to the pressure shown in the Michelin charts and the coach was jumping from grove to grove on the highway and banging at every pothole and ridge. I reduced the air pressure to that listed on the National RV's label.

Result - good ride and handling!

"Always take free advice for what its worth" - me
__________________
J.J. Hayden (KN4SH)
Covington, GA
2005 National Dolphin 5342
JJH3rd is offline   Reply With Quote
Old 03-04-2014, 11:07 AM   #5
Member
 
Join Date: Mar 2014
Posts: 38
Will follow that advice, and put it at the suggested PSI of the manufacture. Also getting ready to install a wireless tire pressure monitoring system, since the wonderful folks at Fleetwood like for us to live on the edge with no spare tire.
__________________
mgjessop is offline   Reply With Quote
Old 03-04-2014, 11:56 AM   #6
Moderator Emeritus
 
RickO's Avatar


 
Join Date: Jan 2007
Location: Litchfield Park, Arizona
Posts: 10,530
Quote:
Originally Posted by JJH3rd View Post
The manufacturer's labels, pasted somewhere in your coach, shows the tire pressure that the manufacturer used in the design of the suspension. Inflate the tires to that pressure for the best handling/ride.
Do you believe this to be true, regardless of what that particular coach weighs?

Rick
__________________
Rick, Nancy, Peanut & Lola our Westie Dogs & Bailey the Sheltie.

2007 Itasca Ellipse 40FD
RickO is offline   Reply With Quote
Old 03-04-2014, 02:56 PM   #7
Senior Member
 
Statgeek's Avatar
 
Fleetwood Owners Club
Freightliner Owners Club
Join Date: Feb 2013
Posts: 1,578
Quote:
Originally Posted by mgjessop View Post
Will follow that advice, and put it at the suggested PSI of the manufacture. Also getting ready to install a wireless tire pressure monitoring system, since the wonderful folks at Fleetwood like for us to live on the edge with no spare tire.
TPMS is always a good idea, regardless of whether or not you have a spare tire. TMPS is meant to help prevent a blowout and alert you to improper inflation or fast changes in pressure so that if you develop a leak you pull over quickly.

For me, I'm happy not to have a spare tire.. I don't in this RV, nor did I have one in the last one. It's not like I can change one myself on a such a rig and then hobble to a garage for proper service. I don't want to store it and drag around the additional weight and volume, and when I need a new tire, chances are that I'll need at least TWO of them to balance the tread wear. So not having a spare tire doesn't bother me in the least.
__________________
2013 Fleetwood Discovery 40G, Cummins ISL,Freightliner Chassis, Allison 3000.
2009 Jeep Wrangler Unlimited Toad w/ Blue Ox Aventa tow bar and M&G Braking System
Statgeek is offline   Reply With Quote
Old 03-05-2014, 02:33 AM   #8
Senior Member
 
jadatis's Avatar
 
Join Date: Oct 2012
Posts: 247
Can calculate it if you give the right data .
Found on next site your specifications , but only gave GVWR of 22000 lbs and not the GAWR's
2008 Fleetwood Fiesta® LX 34N Motorhome : Reviews, Prices and Specs : RV Guide

Best ofcource would be weighing and even better per single wheel(Pair), but as long you dont have that we will have to do with the GAWR's
Then from tire maximum load and pressure needed for that ( maxload xxxx lbs AT yyy psi( cold)) read from sidewall but also speedcode or maximum speed of tire.

In my spreadsheets I use a reserve to the filled in load, and calculate with my own formula wich better takes care that the sidewall deflects the same as when maximum load and pressure for that is on tire, wich is the goal of all calculations. So it gives the highest pressure with still acceptable comfort and gripp, and leaves as much possibel reserve for things like pressure loss in time, misyudging of weight and misreadings of weight and pressure scales, etc.

Here a picture as example for other used, in wich wheel(pair) weighing compared with using GAWR's , see the difference.
To compare , I made the assumed axle load in part 2 the same as part 3 and showed that still 1000lbs weightdifference was possible behind with the 95psi pressure based on GAWR. In part 3 it showes to be 800 lbs difference so within the savety borders.


__________________
jadatis is offline   Reply With Quote
Old 03-05-2014, 09:50 AM   #9
Member
 
Join Date: Mar 2014
Posts: 38
Thank you for that wonderful chart. The tires have a max cold of 110psi. I have the front at 100psi and the rear are 95psi cold. I have very little added weight in the coach, at most 1000lbs with the family loaded up. I run a scan gauge II on the until and in the last 150 miles of driving on the 5 freeway cruising at 55mph with no wind been able to turn 10.25mpg average. I took the coach up to 65mph and the fuel economy dropped to the low 8's. Seems like speed is what I have to watch more than the tire pressure to get the better mpg's. You all have been very helpful and thank you very much for your advice.
__________________
mgjessop is offline   Reply With Quote
Old 03-05-2014, 10:10 AM   #10
Senior Member
 
Ray,IN's Avatar
 
Join Date: Aug 2001
Location: North America somewhere
Posts: 13,686
The RMA Rubber Manufacturers Association, states that over 90% of all tire failures are the result of underinflation/overloading. Running the minimum for your weight by the load/inflation tables, IMO is not prudent.
__________________
2000 Winnebago Ultimate Freedom USQ40JD, ISC 8.3 Cummins 350, Spartan MM Chassis. USA 1SG, retired;PPA,Good Sam Life member,FMCA."We the people are the rightful masters of both the Congress and the Courts - not to overthrow the Constitution but to overthrow men who pervert the Constitution. "Abraham Lincoln"
Ray,IN is offline   Reply With Quote
Old 03-10-2014, 08:39 AM   #11
Senior Member
 
Join Date: Feb 2011
Posts: 514
Quote:
Originally Posted by RickO View Post
Do you believe this to be true, regardless of what that particular coach weighs?

Rick
I agree. I think those posted pressures both on the tire and inside the coach are maximum pressures.I tried those and my dashboard liked to have fell out it rode like a buckboard I usually travel at least 10 lbs under those pressures. I dont care what the rig weighs if I have to travel with those pressures I'm giving the thing up !! Its a gasser of course
__________________
Don and Maxine McQueen
1996 Damon Intruder
F53 Chassis 33 ft
donandmax is offline   Reply With Quote
Old 03-10-2014, 10:09 AM   #12
Senior Member
 
al2ride's Avatar
 
Join Date: Jan 2014
Posts: 1,278
Quote:
Originally Posted by donandmax View Post
I agree. I think those posted pressures both on the tire and inside the coach are maximum pressures.I tried those and my dashboard liked to have fell out it rode like a buckboard I usually travel at least 10 lbs under those pressures. I dont care what the rig weighs if I have to travel with those pressures I'm giving the thing up !! Its a gasser of course
I know that the posted pressure on the actual tire is a maximum pressure, but not sure about the pressure posted on the decal inside the coach. I do know that I have always kept my vehicles tires at the pressure posted on the decal usually on the door jamb or glove box. What I don't know if it's the same thing for a MH because of how much the actual weight can vary.

There has to be somebody that can speak about this with authority. If I had to guess, the pressure posted inside the coach is in direct relationship to the posted weight. Is that the weight of the coach as it was sold without any gear, water, etc.
__________________
USAF Veteran
2014 Forest River Georgetown 351DS
2014 Jeep Wrangler Unlimited Rubicon Toad
al2ride is offline   Reply With Quote
Old 03-10-2014, 10:16 AM   #13
Moderator Emeritus
 
RickO's Avatar


 
Join Date: Jan 2007
Location: Litchfield Park, Arizona
Posts: 10,530
Quote:
Originally Posted by al2ride View Post
There has to be somebody that can speak about this with authority. If I had to guess, the pressure posted inside the coach is in direct relationship to the posted weight. Is that the weight of the coach as it was sold without any gear, water, etc.
I'm no authority on the matter, but I think you're right about the pressures being related to the posted weight... which I suspect is the GAWR or some such number which represents what the rig is capable of carrying.

In my mind, I can't see how the mfgr could specify a PSI which would be optimal for both empty and fully loaded rigs. Therefore, the authority is the tire manufacturer's weight/pressure tables based on the actual weight of your rig.

Rick
__________________
Rick, Nancy, Peanut & Lola our Westie Dogs & Bailey the Sheltie.

2007 Itasca Ellipse 40FD
RickO is offline   Reply With Quote
Old 03-10-2014, 10:34 AM   #14
Senior Member
 
al2ride's Avatar
 
Join Date: Jan 2014
Posts: 1,278
Quote:
Originally Posted by RickO View Post
I'm no authority on the matter, but I think you're right about the pressures being related to the posted weight... which I suspect is the GAWR or some such number which represents what the rig is capable of carrying.

In my mind, I can't see how the mfgr could specify a PSI which would be optimal for both empty and fully loaded rigs. Therefore, the authority is the tire manufacturer's weight/pressure tables based on the actual weight of your rig.

Rick
I'm with you on the tire manufacturer being the final authority based on actual weight.

However, I would like to know what the pressure indicated on the decal is in relation to (max allowable weight, an average weight, or the weight as it leaves the plant).
__________________

__________________
USAF Veteran
2014 Forest River Georgetown 351DS
2014 Jeep Wrangler Unlimited Rubicon Toad
al2ride is offline   Reply With Quote
Reply

Tags
tire pressure



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


Similar Threads
Thread Thread Starter Forum Replies Last Post
Crossfire dual tire pressure adonh Class A Motorhome Discussions 11 01-27-2014 12:02 PM
Accurate tire pressure gauge? WineLuvrs iRV2.com General Discussion 49 01-16-2014 08:35 AM
Recommended Minimum Tire Pressure carolinagirl Winnebago Industries Owner's Forum 43 01-02-2014 08:43 PM
Tire Pressure? Lt. Tiffin Motorhomes Owners Forum 6 07-14-2013 06:23 PM
Tire pressure question AWMIII Newmar Owner's Forum 1 06-12-2013 10:22 AM

» Virginia Campgrounds

Reviews provided by


Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 07:39 PM.


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