FWIW: I run all tire pressures on the truck when towing and the 5'er at the max inflation reflected on the sidewall (80 PSI). Always have, always will.
Happy camping!!! See y'all down the road!!!
2001 35 ft avalon alpenlite RK
2005 3500 2wd duramax CC dually
trailair center point suspension
JT Strong Arm Stabilizers
KSH 55 inbed fuel tank
Induction Overhaul Kit
TST tire monitors
I guess we're talking about the truck tires here. If the truck has the original size tires, the sticker on the door pillar will have the PSI needed when the truck is loaded to the full GVWR. Assuming you are not loaded above the GVWR (you shouldn't be) then you can feel safe running the pressure on the door pillar.
If we're talking about the trailer, I would run those tires at the tire sidewall maximum.
If a deviation is required for towing, follow the recommendations in the truck's owner's manual.
I run 80 front and 55 rear 2011 Ram Dually long bed 36 Mobile suites. 11,000 miles and the tires are wearing very even and showing wery little wear. A friend has a similar setup 30,000 miles he runs 80 all around, his front tires look about 2/3 evenly worn but his back are worn almost to the bars in the center and the edges still have about 1/3 tread. His truck is only used for towing as they have a rice eater for groceries. I use mine about 1/2 for towing and I never change the air pressure. Look at your tire mfg tire chart and you will see that 80 psi is way over inflated for any legal application on the rear with duals.
2011 Ram Laramie Longhorn 3500 Dually Long Bed, Cummins 350/800 HO, Towin Machine
B&W Companion Hitch, Maghytec Trans and Rear Dif Covers, AMZ/OIL Top To Bottom
2007 1/2 Mobile Suites 36 SB3 27,000# Combined
The maximum load of a tire is calculated with the reference-pressure on it , wich is not the maximum pressure of the tire.
If you read "maximum load single/dual xxxx kg/lbs AT yyy kPa/PSI ( cold)" it means that up to the maximum speed of the tire, or if lower 99m/h) the tire may bare the xxxx at the pressure yyy without damaging the tires by driving alone.
The tire then has a deflection that the construction can stand, deflecting and flexing those 10 to 15 times a second, depending on the speed.
If you take care that this deflection stays the same for a lower weight on the tire, you will have the same savety and grip and comfort, as the tire-maker intended.
The tire-makers use a formula for that to calculate the maximum load for a sertain lower pressure, wich is introduced in 1928 for diagonal tires.
About 1970 it is adjusted for radial tires in the power that is used in it, in Europe for all kinds of tires to one that gives pretty save answers, but in America to a lower power , wich gave to much deflection of the tire, wich could give tire damage at higher speed.
As late as 2006 American TRA swiched over to the European power , but not for C-load tires and up , So list for the tires RV's use from American tires still give to high load-capacity for the pressure.
Even the European power gives somewhat to high load-capacity for C-load and up, I concluded from an article of an American J.C.Daws ( so you can trust, never trust this Dutch hobby tire-pressure calculator).
At the bottom spreadsheet "my own formul........ you can make your own loadcapacitylist.
I did not even agree with the calculation J.C.Daws describes, and made my own universal formula, wich is a combination of the old one and his. By filling in the right Lc( construction load) and X ( power to be used) you can still make the old formula and "Daws"formula if you trust them better.
To Download a spreadsheet , click on the line , but not on the name of it, then in the right barr at download. Open after download, and eventual virus-check, in Excell or compatible to use it.
This spreadsheet also works in the browser.
Also in the map a Word document about the still used wrong calculation in America for C-load and up. I ask myself , why they did not change that either in 2006, probably because it did not give problems, because of the lower speeds and over-capacity in the system.
What 5ertime writes about beter braking and his global calculation of the lower pressure in the front is a good way to go.
But mind that a Higher load-letter , fi A G-load versus a E-load, G-load needs a higher pressure for the same load then the E-load, but with my spreadsheet it can all be calculate.
mind to take a reserve in the load-capacity. If you add 10% to the load you want to know the advice pressure for , the ride is still comfortable and good grip, and you have a reserve for the next.
1. misreadings of weight and pressure-scales and misyudging of the weight.
2. shifted load R/L.
3. Incidental extraload or loadshifting during the vacation.
4. pressure-loss in time.
The front axle seldomly goes over its GAWR, but the back axle often does for RV's with lower GVWR ( gross vehicle weight rating) , that are used in Europe often at max 3500kg/7700lbs, for reason of allowing to drive it with Normal drivers licence.
Some even manage to go over the GAWR back, with a RV with a larger GVWR, but mostly then back also stays under it in normal use.
Greatings from Holland ( so sorry for miss-spellings and strange words)
Always use whats on the tire sidewall. The tire manufacturer knows more about their tires than the RV manufacturer.
Or Ford. Had all those SUVs, trucks and vans that crashed, had properly inflated tires, nearly all those crashes could have been avoided. C'mon, inflating tires to 26-28 lbs in a 5-6k lb vehicle? Had I been one of those owners, I would have contacted Ford right away and asked for a "correct" placard. At those inflations, the tires were overloaded when they left the factory.
2002 GMC Sierra 2500 HD Duramax Crew Cab 4x4
Banks Bullet Tuner and Monster Exhaust
B&W Turnover Ball with 5th Wheel Companion
2004 Komfort 25FSG Fifth Wheel
1936 John Deere Model A
International Flying Farmers 55 Year Member
Looks like we have several different answers and if no problems as I have never had a problem doing how we air our tires I guess it doesn't matter how much air pressure is needed.
Well I think we all agree that we need to run at least enough pressure for the load, based on door label or inflation chart by the manufacturer. And we agree that no one should run more than the sidewall maximum. So between one and the other we are only talking about 10 or 15 extra psi, in most cases.
To some degree this personal decision may be based on how you use your truck. If I was full time and carried the fiver all the time, I could see running the pressure up to the sidewall max. There isn't much downside to doing that. But I use the truck most of the time without the fiver, and the sidewall max with an empty truck is a rough ride. For me it is better to follow the label and avoid frequently changing the inflation. Before we bought the fiver, I often ran less than the door label, because the empty truck rode a lot better.