Endurance Tire pressure on 27FB Int'l

[wulfraat]

Originally Posted by brick1

My 2018 Serenity 28 also has factory stickers calling for 80 psi cold. I am following the factory recommendations, as I hope the factory knows what they are doing.

See post #12 above.

[gypsydad]

Originally Posted by brick1

My 2018 Serenity 28 also has factory stickers calling for 80 psi cold. I am following the factory recommendations, as I hope the factory knows what they are doing.

Not much here to say that hasn't been said already, except: I also spoke with a Goodyear "tire expert" on the phone this morning, (after going thru 3 different Goodyear reps. first!) When I asked regarding the PSI vs weight on their charts, he recommended I follow the GYE chart numbers for PSI for weight on my trailer. He said the "max inflate" numbers are a guide since most people don't know their trailer weight. He went on to say, the "composition of materials used in tires vary' greatly from manufacturer, and although there are "other" tire charts out there, best to follow the specific tire manufacturer guide if you know your vehicle weights for best performance.

[jadatis]

Originally Posted by LAWBC

Just replaced original tires on my 27 FB International and set pressure at 70 PSI . I have read where some run lower pressure, my Marathons where 65 PSI and never had a problem with them for 6 years.



The installer tells me that the Endurance are 10 ply where the Marathons where only 6ply.


What tire pressure at cold do you set yours ?

Have seen no further post of topicstarter, would like a reaction from him to.

But to resume it all .
Going from D-load AT 65 psi ( so not C-load (AT 50 psi)) to E-load AT 80 psi, generally would need a bit higher pressure to carry the same load( if sises the same) .
But generally the tires can carry the loads of TT with no reserve, and even ST calculated for lower speed so more load to carry with small tire, and better give pressure a LT tire of same sise would need, so even higher pressure.

But all this is not needed for AS , because tires have ,as exeption to the rule, a comfortable reserve, so can do with lower pressure. Some even had bumping problems with the adviced 65 psi.

My advice is to give me your GVWR, and if tandem or single axle, nice would be the GAWR's
And then the tirespecifications .
Then I will calculate a safe lowest pressure for your used maximum speed, and a highest pressure, with max reserve, and still no bumping.

That is why your Maratons did not give problems, ( even if ST ) because still comfortable reserve)

[Action]

Recommended tire inflation is a function of the vehicle manufacture. There will be a tire decal on the trailer that indicates recommended tire pressures and tire sizes. That would be the best starting point.

The tire manufacture may have some suggestions. Those suggestions would be based on load. If you know the max weight in load one could inflate to that scenario. This would require weighing the trailer and finding out which tire is supporting the most weight. (Typically a trailer is NOT loaded equally either from side to side or from back to front) Pick the wheel location with the greatest load and inflate to that location. And adding adjustments for margin and tire type if needed.

>>>>>>>>>>>>>>>Action

[OTRA15]

The Goodyear Endurance is a fairly new design, so most Airstreams would not have accurate tire pressure info on that decal IMO.

[Action]

Originally Posted by OTRA15

The Goodyear Endurance is a fairly new design, so most Airstreams would not have accurate tire pressure info on that decal IMO.

Why?

A tire doesn't know the difference of what type of trailer it is supporting.
And the trailer doesn't know the difference as to tires.

Tires support weight using pressure. The tire is only impacted by weight. Within the limits of the tire, weight is the only factor for adjusting pressure.

The newer Endurance tires will support more weight than the older tires that were available. That is only because they can handle greater pressure/load. If two different tires were possible - one and 200% of that weight and the other at 250% of that weight, both could be inflated to 115% of that weight and still be good.

Lacking a scaled weight measurement, the AS trailer is designed at a certain running weight. The pressure inflated is what supports the weight. If the recommended pressure is 60 on a tire that max pressure is 80. It would be the same pressure of 60 for a tire that max pressure is 65. That 60 PSI supports the same load no matter what the max pressure of the tire.

>>>>>>>>>>>>Action

[KK4YZ]

Originally Posted by brick1

My 2018 Serenity 28 also has factory stickers calling for 80 psi cold. I am following the factory recommendations, as I hope the factory knows what they are doing.

Well in this case I’m afraid you might be giving the factory too much credit.
For example On a 2017 23D (which came with GYM’s) the sticker says ‘65 PSI’, which is the max pressure for the GYM’s. The exact same 2018 model came with GYE’s and the sticker read ‘80 psi’.... the max pressure for GYE’s.

I doubt the factory did any big time math to come up with those numbers... they just mimicked what was on the tire sidewall.

That being said, some pretty experienced guys on this forum recommend running max sidewall pressure...if your trailer can stand it.

I run my GYE’s in the low 70’s to get a lot of margin (23D FC) and peace of mind. No trouble with cabinets but do get a rivet popped every so often. It’s easy enough to fix.

[Action]

Lacking actual trailer weight data, selecting tire pressure is either reactive based on the previous tow experience. Or towing while blind based on manufacture's data. Especially for trailers that could have a very wide range of loads depending on how the user loads up the trailer.

A user can post I have this trailer (year and model) and looking at the max GVWR that number could be well into 5 digit weights. However that user doesn't load their trailer anywhere near that limit. Which would mean the tire pressure should be dropped. But the next guy with the same trailer loads it very close to max GVRW. That trailer should have higher tire pressures based on actual load.

>>>>>>>>>>>>>>>>Action

[jadatis]

Originally Posted by Action

Why?

A tire doesn't know the difference of what type of trailer it is supporting.
And the trailer doesn't know the difference as to tires.

Tires support weight using pressure. The tire is only impacted by weight. Within the limits of the tire, weight is the only factor for adjusting pressure.

The newer Endurance tires will support more weight than the older tires that were available. That is only because they can handle greater pressure/load. If two different tires were possible - one and 200% of that weight and the other at 250% of that weight, both could be inflated to 115% of that weight and still be good.

Lacking a scaled weight measurement, the AS trailer is designed at a certain running weight. The pressure inflated is what supports the weight. If the recommended pressure is 60 on a tire that max pressure is 80. It would be the same pressure of 60 for a tire that max pressure is 65. That 60 PSI supports the same load no matter what the max pressure of the tire.

>>>>>>>>>>>>Action

Some wise arguments in your 2 posts here
Only the fatt printed is not true.
A 80psi tire is stiffer to hold the higher pressure in, versus the 65psi tire.
By that stiffer construction, the overgoing curve to flat on the ground is larger, so lesser surface-lengt on the ground with same deflection. So to carry same load , the 80psi tire needs a bit higher pressure then the 65 psi tire.
And that is asuming that both have same heatproduction at same deflection, and probably the 80psi tire has more heatproduction at same deflection. Then a snowball effect happens, the 80psi need for instance 65 instead of 60 psi to give same deflection, and that higher pressure gives larger overgoing curve so less surface on ground, so needs for that higher pressure to compensate, so mayby even 70 psi needed for same load on tire.


I attached a paint-picture I made.
There the same for higher pressure versus lower pressure, but also stifness of tire has same effect.

[MandDinSpgTX]

Originally Posted by brick1

My 2018 Serenity 28 also has factory stickers calling for 80 psi cold. I am following the factory recommendations, as I hope the factory knows what they are doing.

Bingo. Checked with AS and with GY and both said the same thing: 80 is the pressure. No need to play with all of the math. These have been super great tires all around. Maybe not the Michelin's, but overall quite happy.

[ROBERT CROSS]

^
Could that be the reason my GYE's at 70-80psi fun cooler than my GYM's at 65psi?
The more deflection the higher the temps.

Bob
🇺🇸

[wulfraat]

Originally Posted by MandDinSpgTX

Bingo. Checked with AS and with GY and both said the same thing: 80 is the pressure. No need to play with all of the math. These have been super great tires all around. Maybe not the Michelin's, but overall quite happy.

See post 12. AS have to tell you that. And if you tell GY that you have a sticker on your vehicle they will tell you to adhere to the sticker. It’s a legal thing.

There is nothing wrong running at 80, you are guaranteed that the tires will perform, it’s just not necessary to run at max PSI, which is why GY publish the minimum recommended inflation chart posted above.

I think this thread has run its course

[Action]

Setting at factory spec is EZ.

If one wants to at least not get into trouble I think it is a difficult argument to change from what the vehicle manufacture has posted.

HOWEVER, the factory has no idea about the end user. In fact when designing things an engineer has to look at worse case scenario assuming the vehicle is used within designed intent. (Sure one could pull the thing at 85 MPH and suffer an adverse event. And that may be considered outside of the design) The variables for the tires are tire load and vehicle speed. An engineer has to consider the user will max the speed and the GVWR to make the tire placard.

If you are not that user, one could "adjust" the tire pressure to the load. However the data needed would be max anticipated tire load. And a tire chart. Then calculating the pressure required …. with a margin. That may be again the same pressure as the tire placard. And for many vehicles it is not. However it may be the MINIMUM pressure. Have a leak, don't check pressure frequently can get one into trouble. And know all of that requires effort which is not the EZ path. Looking for EZ look at the placard.

Also lacking that measured loading data and the tire charts, I default back to the tire placard.

>>>>>>>>>>>Action

[OTRA15]

Originally Posted by wulfraat

. . .
I think this thread has run its course

Nah . . . just send it to the shop to be re-thread!

[jadatis]

But if you want to use a pressure loadcapacity list , use my made.
Will give link to submap on my public map of one-drive that belongs to my hotmail.com adress with username jadatis ( so combine yourselfes if you want to mail me, spamm machinens cant this way).
In that map for every loadrange/AT-pressure a seperate list, and given per tire, axle single and axle dual.
Made these lists with use of spreadsheet I made , in wich I use an even saver formula then the European officially used for every kind of tire.
American TRA stepped over to this formula as late as 2006 , but only for P-tires , for LT they still use a formula that leads to lower pressures for the load so more deflection.
Also the american lists give for one sise all the loadranges in same list.
This is not done in the european system, for every loadrange/At-pressure a seperate list is made.
I also do that in my made list.
Set the formula that tight , that it sertainly wont lead to to low pressures , or to high loadcapacity's, but this could mean still a little bumping.
You can also play with the maximum speed you use and wont go over for even a minute( so be hounest) .
The system for that I described here already, 1 li step for every 10km/6,5m/h.
https://onedrive.live.com/?id=A526E0...26E0EEE092E6DC

Aso in the per tire given map, a pdf with all the loadranges/ATa-pressures .

[AlbertF]

There are a lot of references to the sticker on the outside of the trailer that says 80 psi, but that’s not what I’m reading in the owner’s manual. It clearly points to using tire manufacturers’ load tables to set inflation pressure.

On that basis, my new 22FB requires no more than 55 psi fully loaded.

[OTRA15]

jadatis, to get the OP’s attention, just Quote him/her from an earlier post, instead of using large all caps IMO.

Peter

[SteveSueMac]

Originally Posted by AlbertF

There are a lot of references to the sticker on the outside of the trailer that says 80 psi, but that’s not what I’m reading in the owner’s manual. It clearly points to using tire manufacturers’ load tables to set inflation pressure.

On that basis, my new 22FB requires no more than 55 psi fully loaded.

I’m not 100% sure on this - but if you’re saying that based on cat scale weights of your trailer, I believe your 22FB would require NO LESS than 55PSI. Those load tables are, if I understand correctly, the minimum PSI required for that load - the sidewall max is the max PSI the tire should have cold (which likely coincides with the sticker) since AS doesn’t know how you’re going to load and use your trailer. Plenty has been written here about margins, not all tires getting equal weights, speed, etc.

I’m not a tire expert. I did stay at a Holiday Inn last night however, so..... [emoji3]

[jadatis]

Originally Posted by OTRA15

jadatis, to get the OP’s attention, just Quote him/her from an earlier post, instead of using large all caps IMO.

Peter

Did that in earlyer post , so thougt this might draw more atention.
He has not reacted here since his first post, can be that he gets no mailmessage of new posts.


To AlbertF: did you add 10% for reserve first before looking in the list.
This is to cover unequall load R/L wich is always the case for TT's.

Oh no , in America minimum 10% on pin, and so axle load is 90% of GVWR.
Adding 10% to that 90% gives 99% , is about 100% , so looking back GVWR is also good.
But looking in my made lists , you get about 5psi more so 60psi I estimate will be the advice then.

My goal is to give the tire a minimum deflection, so maximum pressure, at wich gripp is still acceptable and no bumping.
Then if pressure drops in time, or inacurately to high measured, you still ride with save pressure.

[gypsydad]

Originally Posted by AlbertF

There are a lot of references to the sticker on the outside of the trailer that says 80 psi, but that’s not what I’m reading in the owner’s manual. It clearly points to using tire manufacturers’ load tables to set inflation pressure.

On that basis, my new 22FB requires no more than 55 psi fully loaded.

You are correct,; and I agree!

But as usual, the "facts" don't seem to matter for some of the Forum folks...they will argue till the cows come home!

In my earlier post #42, I shared that I too called GY experts directly this week. Took me talking to 3 different departments/experts, before getting to the real recommendation which was: "the sticker Max Pressure PSI's are meant for most people since "most people" don't know what their rigs weigh. If you know, GY recommends you go by their loading chart for PSI. Makes sense to most of us, doesn't it? (or does it??)

jadatis- Your "charts" are fine as a "guide" but using the MFG recommended PSI's for their particular tire seems to make sense, no?

Some folks here seem to be fine and happy with loosing rivets running MAX or 70+ PSI with their Endurance tires. I also carry extra rivets and a rivet gun. But, I will say, after replacing screws in hinges/latches that stripped out, bedroom closet (with TV) coming loose from ceiling mount, closet door and shower door laying on the floor running 70PSI, I choose to follow the GYE chart. No issues last 6K miles on my 28' FC since I installed these tires last summer and adjusted to recommended 45-50PSI. Anyways, to each his own...hope no one "blows" a tire over this thread!