Journey with Confidence RV GPS App RV Trip Planner RV LIFE Campground Reviews RV Maintenance Take a Speed Test Free 7 Day Trial ×
 


Reply
 
Thread Tools Search this Thread Display Modes
 
Old 04-01-2020, 11:47 AM   #1
Winnebago Camper
 
greenchicken's Avatar
 
Join Date: Jun 2017
Posts: 9
Tire Pressure

I have tires that say cold pressure 90 or 100 lbs but my door tag says 70 Cold pressure all the way around, is it ok to run them at 70 all the way around? here is the door sticker... My ride is rough, I know my rig is old though (1999 adventurer)

greenchicken is offline   Reply With Quote
Old 04-01-2020, 12:00 PM   #2
Winnebago Master
 
Goodspike's Avatar
 
Join Date: Jan 2020
Posts: 1,354
Quote:
Originally Posted by greenchicken View Post
I have tires that say cold pressure 90 or 100 lbs but my door tag says 70 Cold pressure all the way around, is it ok to run them at 70 all the way around?
Yes, often tires will have maximum pressures above what the vehicle manufacturer calls for.
Goodspike is offline   Reply With Quote
Old 04-01-2020, 01:06 PM   #3
Winnebago Camper
 
greenchicken's Avatar
 
Join Date: Jun 2017
Posts: 9
Thanks, I just set them at 80 for the rears and 85 for the front... Rides much better now

greenchicken is offline   Reply With Quote
Old 04-01-2020, 01:57 PM   #4
Winnebago Camper
 
Join Date: Mar 2020
Posts: 42
NOT trying to hijack this thread, but I have steel belted Firestone radials on my 88 Chieftain that say 80+, but the door says 60. Can I run them higher than 60? The sidewalls seem to be bulged out too far at 60lbs.
__________________
Monica and Tony
1988 Chieftain
1956 Studebaker Sky Hawk
345 desoto is offline   Reply With Quote
Old 04-01-2020, 02:00 PM   #5
Winnebago Camper
 
greenchicken's Avatar
 
Join Date: Jun 2017
Posts: 9
you are not hijacking I have been digging deeper into this



Lets look deeper at that sticker and what it means GAWR = Gross axle weight rating so that means the maximum legal load I can carry on the axle is 7k on the front and 13.5k on the rear, these are Maximum values and they recommend 70 psi @ Maximum? GVWR is 20.5k and that is the maximum total it can legally weigh going down the road. I wonder how much this sucker weighs empty... Read this article https://rvmiles.com/properly-inflate-tires/
greenchicken is offline   Reply With Quote
Old 04-01-2020, 02:11 PM   #6
Winnebago Master
 
Goodspike's Avatar
 
Join Date: Jan 2020
Posts: 1,354
Quote:
Originally Posted by 345 desoto View Post
NOT trying to hijack this thread, but I have steel belted Firestone radials on my 88 Chieftain that say 80+, but the door says 60. Can I run them higher than 60? The sidewalls seem to be bulged out too far at 60lbs.
You certainly could, and probably nothing bad would happen.

I'm more familiar with cars and light trucks, but with them higher pressures can make the ride a bit stiffer and it can also change the understeer/oversteer. I go to a high end suspension place for my cars and depending on vehicle they may recommend a higher pressure than the manufacturer. The last car they did that with I didn't like it with their pressure--too much oversteer--but I did stay higher than the manufactuer.

I don't see that motorhomes would be different, but the main thing would probably be ride stiffness.
Goodspike is offline   Reply With Quote
Old 04-01-2020, 02:13 PM   #7
Winnebago Master
 
Join Date: Nov 2018
Location: Pflugerville/Austin, Tx
Posts: 7,371
Tire inflation info is all over the place and it isn't always correct. When I started looking at the current RV, I went with the posted info for maximum but I also installed a set of tire pressure monitors and it has given me a very different idea of what my pressure is doing so that I no longer fuss with getting it set at a specific point as i find it is never going to stay that pressure for long! I'm gradually working the pressure down from the specified max as the tires begin to warm almost immediately and the max setting is way rough. Just setting with one side to the sun on a normal day, I se a different reading , depending on which tire is in the sun and one has a tailpipe running near, so that the pressure goes higher on that one before the others.
Tire pressure is a safety item but has a very large amount of slack involved before it becomes dangerous to us or the tires. We start with an estimate of what is best for both ride and wear but rarely does the pressure stay even close to that pressure as it warms.
So I go keeping it moderately full enough to avoid wear but still not get so warm and pressure so high that it comes apart.
Just airing them to the "correct" pressure when it's 40 will way overshoot when it's 80, so unless we see ourselves changing pressure every hour or so, it's never going to be "correct" as specified.
__________________
Richard
Why no RV year, make and floorplan on MY signature as we suggest for others?
I currently DO NOT have one!
Morich is offline   Reply With Quote
Old 04-01-2020, 02:21 PM   #8
Winnebago Master
 
Goodspike's Avatar
 
Join Date: Jan 2020
Posts: 1,354
Quote:
Originally Posted by Morich View Post
Tire pressure is a safety item but has a very large amount of slack involved before it becomes dangerous to us or the tires.
And usually the safety concern is too little pressure, not too much, unless you exceed that number on the sidewall.
Goodspike is offline   Reply With Quote
Old 04-08-2020, 04:42 PM   #9
Winnebago Watcher
 
Join Date: Oct 2019
Posts: 3
Door sticker

I have found that the tire door sticker info is primarily applicable to the original tires . How would the sticker know what brand or type of tires are on the vehicle? Your tire shop guy is likely the best source of advice.
firemangk is offline   Reply With Quote
Old 04-08-2020, 04:58 PM   #10
Site Team
 
creativepart's Avatar
 
Join Date: Sep 2009
Location: Spring Branch, TX
Posts: 7,783
Tony... what's the DOT date on those tires on your 32 year old RV? If 7 years old or older you really should replace them all.

Weren't "Firestone Steel Belted Radials" the tires recalled for safety concerns effecting 1.5 million tires?
__________________
2017 Winnebago Adventurer 37F
2016 Lincoln MKX Toad
creativepart is offline   Reply With Quote
Old 04-08-2020, 04:58 PM   #11
Winnebago Owner
 
Join Date: Feb 2017
Posts: 184
Hey Greenchicken,
A little Easter egg hunt for you.
Winne always glued an 8-1/2"x11" document inside one of your cabinets (an as-built).
It tells you how much it weighed (as-built) and what was special. Also the gross weight.
So go find it!
And happy Easter
__________________
2003 Journey DL Whidbey Island USA
dickb46 is offline   Reply With Quote
Old 04-08-2020, 04:58 PM   #12
Winnebago Owner
 
Join Date: Mar 2010
Location: Akron, Ohio
Posts: 174
Here is a post from my RVTireSafety blog of April 2016
===

If you are new to the RV lifestyle or an old hand with many thousand campfires under your belt, there is one thing that is true: What you knew or learned about tires from years of car ownership probably did not prepare you for the task of maintaining the tires on your RV. This is true if your RV is a 18’ Travel Trailer or a 45’ Diesel Pusher.
I think we all understand the concept that a system is no stronger than its weakest link. For many RVs, the weakest link that can interrupt long term, problem free travel are the tires. Car tires have evolved with improved durability and reliability to the point that many people may never need to touch their tires or even know how to change a tire. Today, some cars don’t even have a spare tire and if they do the driver may not have even bothered to learn where it is as the expectation of needing to use the spare is so low it has completely dropped off the radar screen.
As a retired Tire Engineer with 40 years experience in design, evaluation and quality assurance of tires I would like to offer some suggestions that I believe if followed, will lead to many years of problem free travel. I also believe that once you take the initial steps I outline, you will also find that you will only need to spend about 15 minutes a month, or less on average with tire maintenance.
The basics that are needed to have a tire problem free experience with your RV tires involve two simple steps:
1. Knowing the proper level of tire inflation on your personal RV and
2. Ensuring your tires are always inflated to that level.
There it is, just two simple and rather basic steps and, you don’t need to be experienced in vehicle mechanics or tire engineering to accomplish these two steps as I am going to share the steps that have worked for me and thousands of others for decades.
Step 1: Knowing Your Proper Inflation
So the first step is to know the proper level of tire inflation on your personal RV. The important concept here is “Your RV. Not the RV your brother-in law uses, or the inflation the guy in the campsite next to you uses, or even the level provided by the RV manufacturer on the tire certification label, otherwise know as the “Tire Placard”. Now some will point out that the RV manufacturer has the responsibility to inform you of the minimum tire inflation you should use, and this is correct, but this is based on an assumption which may mean the numbers are too high or too low for your RV when you have it packed with the stuff you want to take along on your next trip.
This step takes the most effort, but you really only need to do it once over the years you own your RV – unless you make a major change such as add a generator or refinish the interior with granite counter tops; you know, do something that significantly changes the weight of the RV.
To learn your real weight you need to pack your RV with all the clothes, food, fuel, water and other “stuff” you expect to carry, including the proverbial "bowling ball collection." Once it is fully loaded, you and the family need to take a short trip to a local feed store or gravel pit or truck stop that has a large truck scale with enough side clearance that will allow you to get the tires from just one side of the RV on the scale. Obviously you will need to do a bit of preparation to find such a scale, so some time on the Internet or with a phone book is in order. It is suggested that you review the worksheet before heading off to the scale so you get all the facts you need in one trip.
Here is a company that travels the US and specializes in properly weighing RVs and giving the owner the load numbers for their personal unit. " RV Safety & Education Foundation (RVSEF) This leader in safety education in the RV community offers wheel by wheel RV weighing services for all types of RVs.
Resources
If you will not be in one of the locations where RVSEF is offering their services then you will need to do a little research, as not all truck scales have the side clearance needed. You should know that some truck scale operators discourage side to side weights and have installed guard rail to prevent this. When you check out the work sheet you will have a better understanding of what is needed.
Our friends at Fifthwheel St have a web site has information including a video that focuses on trailers but has video showing the process which is similar for motorhomes.

Bridgestone has a page just on RV tires with a worksheet for calculating tire loads

Goodyear has a nice site too

Here is the Michelin RV tire page

If you look at more than one of the above links I think you will see that everyone offers the same basic information on the process. You do not need to worry about which worksheet you use as the math is the same for everyone.
After you complete your worksheet you should know the actual load on each tire position. The next step is much easier and also only needs to be done once. You need to confirm the minimum cold inflation your tires need to carry the load. It is always a good idea to use the tables published by your brand tire. Here is my blog page with links to many different brand tires. Simply go to your brand, find the table that has your size tire and look for the inflation that supports your load or more. Don't worry if your brand doesn't offer tables as almost all companies follow the same published industry standards.
Also don’t be tempted to go to a lower level of inflation if your numbers are close. Always go up.
Now you know the minimum Cold Inflation Pressure or CIP. Wait! What do I mean by CIP? Whenever tire inflation pressure is measured or set the tire needs to be cool and at the same temperature of the air and in the shade. This means not having been driven on or in direct sunlight for at least 2 to 3 hours. Tires get warm when moving and the Sun heats them up which results in a higher temperature which results in artificial increase in pressure. Many people simply do their tire pressure check in the morning before starting out or late evening after a day of travel. Either way the tire needs to be cool and in the shade when you check your pressure.

I feel the CIP needs to above the minimum needed to carry the load as if there is a drop in temperature you may end up below the minimum if you cut things too close. I suggest you run +10% above the Minimum for your personal CIP.
A couple of details and a suggestion:
All tires on each axle should have the same inflation. This means that whatever inflation numbers you have for your tires select the highest from the tires on any one axle and use that number for all tires on that axle. This will give you more uniform stopping and steering response.
Over the past few years technology has evolved that allows you to monitor your tire inflation as you drive down the road and can warn you if you pick up a nail or other damage. You have this in your car and it is that little orange symbol with the exclamation point in it.
and now you can add this safety feature to your RV trailer or motorhome. It is called a Tire Pressure Monitor System or TPMS for short. A quick internet search will identify a number of units specifically designed for RV application or you can review THIS web site for a discussion of features to consider when shopping for a TPMS.
A bit of Truth in Advertising here. This blog is currently sponsored by Tire Traker brand TPMS. As you might expect that is the brand I have run for years. What you may not know is that I bought my TPMS from Traker before I started writing this blog.
One nice feature of having such a system is you do not need to get out with your digital pressure gauge and check your tires every day of travel as the TPMS will let you know your inflation in the morning while you stay inside with your coffee and more importantly while going down the road. You will quickly learn the details of your pressure reading in just a few days of observation.
So there you have it. Get the RV weighed when fully loaded and do the calculations using the worksheet to learn the actual tire loading and the inflation your tires need.
Step 2: Ensuring That Inflation Is Properly Maintained
This step is much more straightforward. Just check your tire pressure every travel day, or better yet get and use a TPMS (Tire Pressure Monitoring System)to constantly monitor your tire pressure. I even set my low pressure alarm level so I would get a warning before the pressure drops below the minimum inflation I need to support the measured load on my RV.
I believe that if you follow this advice you should reduce what otherwise might be a less than 5% chance of having a tire failure to less than ½% chance of tire failure.
__________________
Retired Design & Quality Tire Eng. Have a tire blog RVTireSafety.NET Scheduled to give tire seminars at FMCA Convention in Tucson March 20 - 22, 2024
Tireman9 is offline   Reply With Quote
Old 04-08-2020, 05:00 PM   #13
Winnebago Owner
 
Join Date: Feb 2017
Posts: 184
Oh! And great looking rig!
__________________
2003 Journey DL Whidbey Island USA
dickb46 is offline   Reply With Quote
Old 04-08-2020, 05:17 PM   #14
Winnebago Owner
 
Join Date: Feb 2017
Posts: 184
And I love your dog!
__________________
2003 Journey DL Whidbey Island USA
dickb46 is offline   Reply With Quote
Old 04-08-2020, 05:57 PM   #15
Winnebago Master
 
Join Date: Oct 2017
Location: Elk Grove, CA
Posts: 3,574
Go with Tireman9's post, you don't need anyone else's opinion, listen to the expert.
__________________
Bob C
2002 Itasca Suncruiser 35U
Workhorse Chassis
BobC is offline   Reply With Quote
Old 04-08-2020, 06:14 PM   #16
Itasca Meridian 32T
 
Join Date: Apr 2019
Posts: 7
Tireman9 has all the right info on what tire pressure is about.
It's not what the label says!
IMDiesel is offline   Reply With Quote
Old 04-08-2020, 07:24 PM   #17
Winnie-Wise
 
Join Date: Apr 2000
Location: Waynesboro,PA USA
Posts: 307
Yup listen to tireman and weigh your rig. None of our rigs ever took the tire pressure on the door.
__________________
Downsized Winnebago C, 24 V /08 Saturn Vue/2014 Town and Country Van/03 Goldwing (Big Red)Recently triked Roadsmith kit
Beabop is offline   Reply With Quote
Old 04-09-2020, 03:25 AM   #18
Member
 
Join Date: Oct 2012
Location: Tilburg, Holland
Posts: 64
Tireman 9 already wrote to your satisfaction, but this " Dutch Pigheaded selfdeclared tirepressure-specialist" wants to give his input too, for what it is worth. No professional in tires, yust one of my projects in wich I kept hanging for 13 years now.

Googled your sise tire in F-load to be Loadindex 129 AT 95psi, and 128AT 95 for dual load( your RV rear ) . Pigheadedly lowered Dual to 127 LI , because in Europe mostly 2 LI steps lower, in USA even 4 steps lower often.

Then I put this ,together with GAWR's in my made extra safe calculator, and it gave front 86psi and rear 93psi.

Then 5% front reserve added to the GAWR , because front seldomly overloaded, and rear 11% adding, because behind often overloaded, so this is maximum pressure at wich comfort and gripp is still acceptable, if you realy drive with axles loaded to GAWR's. But this isEuropean situation, American RV's , with high weightcapacity's , often stay below GAWR's and sometimes front overloaded a bit.
But the reserve-adding is also to cover unequall weight R/L on the axle. Often this weightdiffernce is crossed between the axles, so if you weigh and front fi right more heavy, and rear left more heavy, dont think you did something wrong. But for the pressure advice it dont matter, because both tires on the axle , same pressure.

You already lowered to F 80 and R85psi, and noticed better comfort.

Draw your own conclusions.

Next what I saw, that fi Michelin, only had this sise in H-load AT 120 psi with belonging higher maxload/ LI. And the Goodyear list , of wich I determined the F-load, was in a list of G-load.
American system puts them in one pressure/loadcapacity-list, but European system makes for every loadrange( plyrating EUR system) a seperate P/LC list, in wich higher maxload/LI gives lower loadcapacity for same pressure, or higher pressure for same loadcapacity.

So look at sidewall of your tires, and search for something like LRF/F-load/ 12PR ( replace F/12 for G/14 or H/16). Or better something like xxxx lbs AT yyy psi, because sometimes tiremaker uses different pressure behind AT then belonging to loadrange/plyrating. Standard is E/80psi,F/95psi, G/110psi, H/120 psi.

I now took the F-load from your OEM tires on the plate., but if higher other loadrange, I have to recalculate.

Weighing the way Tireman9 directed to, is better, but as long as you did not do that, you have to use the GAWR's, so you most likely wont have to low pressure.

When you go weighing fully loaded dont forget to fill the watertank, a weight of importance.
jadatis is offline   Reply With Quote
Old 04-09-2020, 07:34 AM   #19
Winnebago Master
 
Goodspike's Avatar
 
Join Date: Jan 2020
Posts: 1,354
Weighing is easy using the Cat Scale sites. Cat has two separate apps, one to find the sites and one to use the site you pick. It costs $12 and can give you front/rear weights in one weighing (or trailer/front tow/rear tow on trailers). Just set up your account and plug in your credit card info before you get there so that you can drive right on.

https://catscale.com/cat-scale-locat...AaAumfEALw_wcB

FWIW, I would never go below what the manufacturer recommends even if your weights do not call for that high of pressure for the tire to carry safely carry the weight. The recommended manufacturer pressures have to do with more than the tire being able to carry the weight. They are also about tread wear and handling.
Goodspike is offline   Reply With Quote
Old 04-09-2020, 09:42 AM   #20
Winnebago Master
 
Join Date: Oct 2017
Location: Elk Grove, CA
Posts: 3,574
Quote:
Originally Posted by Goodspike View Post
FWIW, I would never go below what the manufacturer recommends even if your weights do not call for that high of pressure for the tire to carry safely carry the weight. The recommended manufacturer pressures have to do with more than the tire being able to carry the weight. They are also about tread wear and handling.
I'm not sure what you're saying. If you use a weight/pressure table from your tire manufacturer, the pressures are "recommended manufacturer pressures". I agree that if your weights are below the minimum weights on the table, you shouldn't go below the lowest pressure listed.

On the other hand, if you saying that one should never go below the pressures on the door placard, I respectively disagree.

Is it a safe practice, yes, is it a necessary practice, no.
__________________
Bob C
2002 Itasca Suncruiser 35U
Workhorse Chassis
BobC 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
Tire Pressure ? steve R Running Gear, Axles, Brakes, Wheels and Tires 10 01-26-2009 07:03 PM
MPG and Tire Pressure KIX Running Gear, Axles, Brakes, Wheels and Tires 16 11-12-2007 01:36 PM
checking tire pressure.. gary two Running Gear, Axles, Brakes, Wheels and Tires 9 10-25-2007 04:24 AM
what's a good rule of thumb tire pressure? BradandJanee Running Gear, Axles, Brakes, Wheels and Tires 16 01-02-2006 07:22 AM
Conflicting Tire Pressure Recommendations chazfaz Running Gear, Axles, Brakes, Wheels and Tires 12 01-27-2005 03:37 PM

» Featured Campgrounds

Reviews provided by

Disclaimer:

This website is not affiliated with or endorsed by Winnebago Industries or any of its affiliates. This is an independent, unofficial site.


All times are GMT -6. The time now is 08:37 PM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.