Do I really need 80 psi in my rear tires?

[jadatis]

When I use my made motorhome-tirepressure-calculator, it ads first 10% to the given axleload for reserve.
If you use the 5291 lbs GAWR you gave, it would mean 5820 lbs for wich my spreadsheet calculates the pressure, with my determined formula, that leads to higher pressures then the officially used.
Then still comfort and gripp is acceptable.

But why do you think you dont use the GAWR, estimating the axleweight is dangerous, and weighing might prove that you are even overloaded.

Front though is seldom overloaded, so can do mostly ( again dangerous prediction) with much lower pressure.
And bumping on front can also be felt in the back.

So first weigh fully loaded, also all the persons in it, best per axle-end, second best per axle.
Then give those weights here, together with the tire-specifications( 5891/2 lbs AT 80 psi upto 99mph, I concluded of the info you gave), and I will put it in my spreadsheet.
Then most likely it will explain the bumping, and you can chanche the pressures front and back on a safe way.
Now a lit unsertain, so based on that can give tire-failure.

You dont have dualload axxle behind by any chanche, then it would explain the bumping.

[jadatis]

Other explanation is , that your wife and dog are seated behind the rear axle, then the ride is also wilder, and not tire-related.

How did your dog let you know the ride was bumpy?

[dkoldman]

Originally Posted by Wyatt

Legal coverage. “Hey, We warned you”...

I have a box of fire starters that say, “DO NOT USE NEAR FIRE OR FLAME”.

Go figure.

I bought a very nice AstroAI Digital Pressure Meter

To my astonishment, it said to keep away from Fire and Corrosives liquids

This is where I store it now...

[dkoldman]

I read on another forum someone stating the run 85 psi on front axis and 80 psi on the rear duallies...

Then a few others chimed in saying they agree that it is smoother ride. If true, anybody know why that would be the case?

I am planning a 2,000 mile trip and wanting to try this.

[misteracng]

Well it really depends on the coach and the tires, my tires are max 80psi cold so that’s the limit and would not give a good ride at all and is not needed. but if you have say 22inch wheels or something then 80 would not be considered high it might be just right based on the weight and the coach specs

[kmessinger]

They are seated in front of the rear axle. My dog told my wife . . . I didn't ask.

[dkoldman]

Originally Posted by misteracng

Well it really depends on the coach and the tires, my tires are max 80psi cold so that’s the limit and would not give a good ride at all and is not needed. but if you have say 22inch wheels or something then 80 would not be considered high it might be just right based on the weight and the coach specs

My coach says 82 psi for all 6 tires. Basically all my autos are 34 or 35 psi and they are all different shapes, sizes and tires. Sometimes the cars / SUVs are loaded and sometimes they are not. But for an RV.... it is nightmare if you start talking air pressure

I have Ford F-53 that you would think is common but not really so. Took forever to find a windshield wiper blade, and when I did; I didn't buy it because I don't need special just normal.

But where I was really going is if there was something that could explain why have air on front axles 5 psi higher than the rear? If true benefit, seem like it would be true across the board on all vehicles.

FWIW, I did find site where I saw that claim and I asked why and they gave me the below response.

By reducing the tire pressure you are increasing the effective runtime caster trail. This is similar to increasing the caster angle.

So I am still as confused as before

In the meantime, I will drive it with 85psi (87psi @70degrees) fronts and 80psi (83psi@70degrees) rear and see what happens
.