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

Go Back   Montana Owners Club - Keystone Montana 5th Wheel Forum > GENERAL DISCUSSIONS > TIRES, Montana Tires
Click Here to Login

Reply
 
Thread Tools Search this Thread Display Modes
 
Old 12-09-2019, 06:58 PM   #1
masterdrago
Montana Master
 
masterdrago's Avatar
 
Join Date: Sep 2017
Location: Willis
Posts: 896
M.O.C. #20587
Am I Doing This Wrong - Tire Inflation

I looked around on this and a few other RV forums but got no clear answer. I've always inflated my Sailun St235/80R16 to near max - 110psi. When I had my individual wheel weight taken, I was told to inflate to the load. Well, the load is different on each tire. See load & margins....






If you take a look at the charts and weights, I should have the tires inflated from 60-85 psi, not 110, depending on which tire When inflated at those levels, the tire does not look right and will have extremely high wear on the outside edges. What does this experienced crowd think?
 
__________________
2018 Montana 3791RD (SOLD)
2017 Ram 3500 DRW 6.7 Cummins Aisin, B&W RVK3600 (SOLD)
masterdrago is offline   Reply With Quote
Old 12-09-2019, 07:47 PM   #2
DQDick
Site Team
 
DQDick's Avatar
 
Join Date: Jun 2011
Location: Wilsey
Posts: 18,799
M.O.C. #11455
Never have inflated to the load. Always inflated to about 108. We're close to 90,000 miles now on two rigs and it works for us so we'll keep doing it.
__________________
Dick, Joyce, Diego, Picatso and Gustav
2017 3720 RL, and 2013 HC 343RL
Pullrite Hitch, IS, Disk Brakes, 3rd AC, Winegard Traveler, Bathroom door mod, Dometic 320, couch for desk swap, replaced chairs, sun screens, added awnings, etc.
DQDick is offline   Reply With Quote
Old 12-09-2019, 08:04 PM   #3
rohrmann
Montana Master
 
rohrmann's Avatar
 
Join Date: Oct 2012
Location: Box Elder
Posts: 4,672
M.O.C. #12947
As long as I am at between 105 and 110, hopefully closer to 110, I'm happy and our tires wear just fine. I have read that you should take the highest loaded wheel, add 10% to that and inflate all the tires to that weight on the chart. If you don't want to mess with that, you just inflate to the max cold pressure on the sidewall. I figure, the little extra pressure will reduce the rolling resistance a little bit more than the lower pressures and it will make towing easier and maybe save a little bit of fuel.
__________________
Bob & Becky
2012 3402RL
2012 Chevy 2500HD D/A CC 4WD
rohrmann is offline   Reply With Quote
Old 12-10-2019, 05:04 AM   #4
jeffba
Montana Master
 
Join Date: Oct 2017
Location: Bastrop
Posts: 2,892
M.O.C. #20753
I inflate to the sticker on the side of the camper
__________________
Mocha, one-eyed toothless, hurricane survivor, Pirate dog
2019 20th Anniversary Edition 3701LK
B&W 20K for Ford OEM Puck
2018 Ford F-350 Lariat CCLB PSD DRW KJ5CQH
jeffba is offline   Reply With Quote
Old 12-10-2019, 06:53 AM   #5
masterdrago
Montana Master
 
masterdrago's Avatar
 
Join Date: Sep 2017
Location: Willis
Posts: 896
M.O.C. #20587
Quote:
Originally Posted by jeffba View Post
I inflate to the sticker on the side of the camper
Same here until just now hearing this new thought from https://rvsafety.com/ when we did the individual wheel weights in Buda, Texas. Their web page does not list Sailun. My Sticker and max on tire say 110 and I've been doing for two years. I've always checked the cold pressure at around 70 degrees in the early morning b4 running up the road unless it is crazy cold. Then I let the TPMS relay the pressure and scream that they are low, then cancel it and roll and watch. In really hot weather on the sunny side, I've seen near 125psi. Asked my guys at Discount Tire since I could not reach Sailun and they said that "over pressure" was designed into the tire. Their similar brand is Heartland. So, I'm sticking with the way I've done from the beginning. Thanks for the "pro" answers.
__________________
2018 Montana 3791RD (SOLD)
2017 Ram 3500 DRW 6.7 Cummins Aisin, B&W RVK3600 (SOLD)
masterdrago is offline   Reply With Quote
Old 12-10-2019, 07:23 AM   #6
mazboy
Montana Master
 
Join Date: Aug 2009
Location: Grand Rapids
Posts: 1,896
M.O.C. #9561
Same here....inflate to near the rated pressure...
mazboy is offline   Reply With Quote
Old 12-10-2019, 08:26 AM   #7
ChuckS
Montana Master
 
Join Date: Dec 2017
Location: Mountain Home
Posts: 827
M.O.C. #20949
If you have heavy wear in outside edges of those Sailuns it’s not caused by running 110 psi cold. Furthermore to run those Sailuns at less than 105 is negating the load capacity of the tire and causing the sidewalls to flex.. This in turn will create heat build up and cause issues.

Run them between 105 and 110 and if your axle alignment is good they will wear very even across from edge to edge
ChuckS is offline   Reply With Quote
Old 12-10-2019, 10:16 AM   #8
Skw774
Montana Fan
 
Join Date: Dec 2017
Location: Sharpsburg
Posts: 202
M.O.C. #20974
if inflate to load was the case you would be adjusting your tire pressure all the time on your car. depending on how many people get in and ride that day
__________________

2023 GMC 2500 HD AT4
2018 High Country 340BH
Skw774 is offline   Reply With Quote
Old 12-10-2019, 10:38 AM   #9
Dave W
Montana Master
 
Dave W's Avatar
 
Join Date: Jul 2014
Location: Upstate NY
Posts: 1,788
M.O.C. #14547
I've seen where others on a different and SOB forum did that same set of calculations. Their choice, their time. I just inflate to the max tire capacity psig and have --- for a long time. No wear, rear or worry. My truck - heavier on the LH side with me, a DEF and fuel tank. I still inflate at sticker when towing and 5 psig less when not. I would go 5-8 psig less but the TPMS will tell me I have a low tire.
__________________
Dave W
2014 Montana High Country 343RL (Sold!)
2011 Ford 6.7 Lariat CCLB (Went to PU Heaven)
2019 F150SC XLT SE Sport,w/full tow package
Dave W is offline   Reply With Quote
Old 12-10-2019, 03:03 PM   #10
mlh
Montana Master
 
Join Date: Oct 2004
Location: Salem
Posts: 7,520
M.O.C. #2283
Relax. You are making this way too complicated. The chart gives you the pressure you can carry a load safely. You can carry the same load safer with little heat build up at max pressure.
Lynwood
__________________
www.harrellsprec.com
Lynwood Harrell
323 RL HC 2008 F250
mlh is offline   Reply With Quote
Old 12-10-2019, 03:09 PM   #11
7.3Ford
Montana Master
 
7.3Ford's Avatar
 
Join Date: Oct 2009
Location: Indian Land
Posts: 1,142
M.O.C. #9808
I ordered my 5th wheel with G-614, and the sticker Montana put on my trailer says 110 psi, so that is what I always do.
__________________
2015 Montana 3611RL - 2020 RAM 3500 SRW 4X4
John Walker, Indian Land, SC
Blog https://RoVIngWalkers.blogspot.com/
7.3Ford is offline   Reply With Quote
Old 12-10-2019, 07:11 PM   #12
BB_TX
Montana Master
 
Join Date: Oct 2006
Location: McKinney
Posts: 7,122
M.O.C. #6433
I tend to believe the tire manufacturers and tire dealers publish load vs inflation charts because of their expertise, not just something to pass the time. While inflating to the max stated pressure is certainly better than being under inflated, max pressure probably most often falls in the category of over inflated.

Tire manufacturers and dealers information are typically fairly consistent in the following statements;
Under inflation will cause tire over heating
Under inflation will cause increased edge wear
Over inflation will cause a harsher ride
Over inflation will cause increased center wear
Over inflation will cause a harder tire making it more prone to damage and puncture due to impact
Correct inflation for the load provides more even contact to the road across the width of the tread meaning best traction also meaning better braking

If weights are not known then max is the safe way to go. And easiest. If individual weights are known, then it is generally recommended to inflate all tires to the pressure (or slightly higher) recommended for the tire carrying the most weight.
__________________
Bill & Patricia
Riley, our Golden
2007 3075RL (recently sold, currently without)
BB_TX is online now   Reply With Quote
Old 12-11-2019, 04:58 PM   #13
CalandLinda
Montana Master
 
CalandLinda's Avatar
 
Join Date: Jan 2015
Location: Taylors
Posts: 562
M.O.C. #15948
Quote:
Originally Posted by masterdrago View Post
I looked around on this and a few other RV forums but got no clear answer. I've always inflated my Sailun St235/80R16 to near max - 110psi. When I had my individual wheel weight taken, I was told to inflate to the load. Well, the load is different on each tire. See load & margins....Tire industry standards state, in part, that all tires on a single axle need to be inflated to the one carrying the highest load. Notice I said "in part". That's because there is more to it than that and I may touch on it later, below or in another related post.






If you take a look at the charts and weights, I should have the tires inflated from 60-85 psi, not 110, depending on which tire When inflated at those levels, the tire does not look right and will have extremely high wear on the outside edges. What does this experienced crowd think?
your "charts and weights" must be used in conjunction with established standards. When inflating your tires to the load carried they have no load capacity reserves.
CalandLinda is offline   Reply With Quote
Old 12-11-2019, 05:23 PM   #14
CalandLinda
Montana Master
 
CalandLinda's Avatar
 
Join Date: Jan 2015
Location: Taylors
Posts: 562
M.O.C. #15948
Quote:
Originally Posted by BB_TX View Post
I tend to believe the tire manufacturers and tire dealers publish load vs inflation charts because of their expertise, not just something to pass the time. While inflating to the max stated pressure is certainly better than being under inflated, max pressure probably most often falls in the category of over inflated.

Tire manufacturers and dealers information are typically fairly consistent in the following statements;
Under inflation will cause tire over heating
Under inflation will cause increased edge wear
Over inflation will cause a harsher ride
Over inflation will cause increased center wear
Over inflation will cause a harder tire making it more prone to damage and puncture due to impact
Correct inflation for the load provides more even contact to the road across the width of the tread meaning best traction also meaning better braking

If weights are not known then max is the safe way to go. And easiest. If individual weights are known, then it is generally recommended to inflate all tires to the pressure (or slightly higher) recommended for the tire carrying the most weight. How about the next trip? Or the one after that? Or the return trip? Did you add water and not dump it? Going to the load carried just might require a trip to some scales that can give you individual wheel loads for every trip. Doesn't that sound a little commercial? Yup, that's because it is.
What is the start of "under inflated" or "over inflated". Something must have been established to have such descriptions. Just maybe it's the vehicle manufacturer's recommendation. Just for the record, those vehicle manufacturer recommendations for the OE tires are considered MINIMUM. They may be best described in this statement. Any tire found with an inflation pressure 20% below recommendation is considered to be in a "run flat" condition and should have an internal inspection to determine damages.

On the other end; tires inflated above what is shown on their sidewall may be "over inflated"

RV trailer tires are not required to have the load capacity reserves the auto industry provides with their vehicles. RVIA has stepped-in with a 10% load capacity reserve policy/recommendation above vehicle certified GAWRs for all RV Trailer OEM tires. However, it's probably not going to be enough, in many cases, because RV trailers are notorious for having at least one wheel position with an overloaded tire.
CalandLinda is offline   Reply With Quote
Old 12-11-2019, 05:49 PM   #15
JABURKHOLDER
Montana Master
 
JABURKHOLDER's Avatar
 
Join Date: May 2016
Location: Cuyahoga Falls
Posts: 698
M.O.C. #18572
Let’s look at this more practically. Do you own four individual wheel scales ?
If not, do you want to purchase them ? Do you want to park on individual wheel scales every time you set up at a campsite ?
How about this; do I check the weight before or after I dump ? Do I weigh every time I take something out of the fridge ? Do I weigh with the slides in or out ?
Too much !
I have a 2016 3791RD with the g-614’s and inflate ALL tires to a minimum of 105psi.
Firm believer in kiss
__________________
ATC/NAC Jerry A. Burkholder, USN (RET.)

Rule #1. The Chief is always right.
Rule #2. When in doubt, refer to rule #1.
JABURKHOLDER is offline   Reply With Quote
Old 12-12-2019, 01:13 PM   #16
uhftx
Montana Fan
 
Join Date: Nov 2004
Location: Hudson
Posts: 480
M.O.C. #2446
Look at your car or suv. The max pressure on the sidewall may state 32 but the MFR of the car states the tire pressure is different for the front two tires vs the rear two tires or something close. IT could be 24 rear and 27 front. This to get even tire wear. Generally the front of the car or Suv is heavier due to engine and front passenger weights.


The tires on our RV units are closer together than the distance on a car truck or suv. So they should most likely be the same all around with only a few inches.


I just purchased 5 sailun tires and 4 rims. My old ones were 80PSI rims. My 3255rl has a max rating of 12,600 or maybe 12,800. I don't remember exactly. I switched because my trailer had LT tires and the load range D Tires were still causing a few blowouts (most likely due to age and sitting in the yard) But I liked the fact that Load Range G was an option. Even thought I do not need to go to 110PSI. I now have a huge margin of safety. And maybe a softer ride for the camper with something less than 110PSI with my mind at ease. Which is what it is all about. NOw I just have to retire and enjoy life.



Here is what I heard from an old timer construction equipment repair guy. IF you jack up each axle and place a contact sheet. (He used and example of black construction paper arts and crafts type. Sprinkle it with flour and put the tire down off the jack) Jack it back up and gently remove the sheet and measure the square inches of the tire impression Length X Width equals area. Take the tire pressure in Pounds Per Square Inch. Divide your contact area number from above and divide that by the tire pressure and you will be within 10 to 15% of the actual weight of the equipment. This works even if you have 4 or 6 or more tires. You could get the weight of everything without having to go to a commercial scale Of course he always claimed he was under 10% error. Just make sure you are on a level hard surface, NOT MUD or gravel.
__________________
Chris Donna and Oliver the rescue Dog.
Old 3255RL It is a weekend warrior and less than 15K miles. Mostly sits at the house. Home is where the heart is.
uhftx is offline   Reply With Quote
Old 12-13-2019, 05:58 AM   #17
masterdrago
Montana Master
 
masterdrago's Avatar
 
Join Date: Sep 2017
Location: Willis
Posts: 896
M.O.C. #20587
Quote:
Originally Posted by JABURKHOLDER View Post
Let’s look at this more practically. Do you own four individual wheel scales ?
If not, do you want to purchase them ? Do you want to park on individual wheel scales every time you set up at a campsite ?
How about this; do I check the weight before or after I dump ? Do I weigh every time I take something out of the fridge ? Do I weigh with the slides in or out ?
Too much !
I have a 2016 3791RD with the g-614’s and inflate ALL tires to a minimum of 105psi.
Firm believer in kiss
As usual, Burk, you make clear and concise points. So no to all.... thanks but I always weigh AFTER I take a dump
__________________
2018 Montana 3791RD (SOLD)
2017 Ram 3500 DRW 6.7 Cummins Aisin, B&W RVK3600 (SOLD)
masterdrago is offline   Reply With Quote
Old 12-15-2019, 01:33 PM   #18
Bill M
Seasoned Camper
 
Join Date: Dec 2018
Location: Jefferson
Posts: 72
M.O.C. #23206
Although Sailuns can be filled to 110 psi, are your rims rated for that 110? If not you are limited to 80 psi & 65 mph max speed. Run at max cold pressure period.
Bill M is offline   Reply With Quote
Old 12-15-2019, 02:27 PM   #19
CalandLinda
Montana Master
 
CalandLinda's Avatar
 
Join Date: Jan 2015
Location: Taylors
Posts: 562
M.O.C. #15948
Quote:
Originally Posted by Bill M View Post
Although Sailuns can be filled to 110 psi, are your rims rated for that 110? If not you are limited to 80 psi & 65 mph max speed. Run at max cold pressure period.
Inflation pressures and speed ratings abide to their own individual standards.

Recommended cold tire inflation pressures for RV trailers are set by the trailer manufacturer and are minimum requirements.

Tire speed ratings are set by individual tire brand manufacturer's. At their maximum value - maybe 75 MPH - they provide 100% of the tire's maximum load capacity.

RV trailer tires without some form of speed limit displayed on their sidewalls default to the TRA standard, 65 MPH.
CalandLinda is offline   Reply With Quote
Old 12-15-2019, 03:27 PM   #20
laverdur
Montana Fan
 
Join Date: Nov 2011
Location: Albany
Posts: 406
M.O.C. #11972
I agree with rohrmann. I run my G614s at 110 psi. I get great wear and good fuel economy, considering the load. Any one who has upgraded from LR E tires to LR G tires should ignore the manufacturer's sticker on the RV. It will say 80 psi when it needs to be higher.
__________________
2012 3150RL. G614 tires. Hardwired surge protector. Level-Up Hydraulic leveling.
2013 F-350 Lariat 6.7 PSD SRW SC LB 4X4 OEM hitch, air self-leveling on rear. 57-gallon replacement fuel tank. DieselSite water separator/fuel filter.
laverdur is offline   Reply With Quote
Reply

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
Forum Jump

» Featured Campgrounds

Reviews provided by

Powered by vBadvanced CMPS v3.2.3
Disclaimer:

This website is not affiliated with or endorsed by Montana RV, Keystone RV Company or any of its affiliates. This is an independent, unofficial site.


All times are GMT -6. The time now is 08:41 PM.


Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2024, vBulletin Solutions, Inc.