Tire inflation

[CWJK55]

The placard inside the drivers for on my 2004 class C recommends 65psi for the front tires and 80 psi for the rear dualies.
The tires front and back list 80psi maximum for each tire.
When I had the vehicle checked out in the summer the guy at the tire site said that they always inflate RV tires on motorhomes to 80psi all the way around.
We're getting ready to head south in a few days and I just filled all of the tires to 80psi.
Which way do most of you go for inflation: manufacturers door placard or tire rating?

[sewmun]

Originally Posted by CWJK55

The placard inside the drivers for on my 2004 class C recommends 65psi for the front tires and 80 psi for the rear dualies.
The tires front and back list 80psi maximum for each tire.
When I had the vehicle checked out in the summer the guy at the tire site said that they always inflate RV tires on motorhomes to 80psi all the way around.
We're getting ready to head south in a few days and I just filled all of the tires to 80psi.
Which way do most of you go for inflation: manufacturers door placard or tire rating?

This has been discussed many times.BUT if you look @ the tire you'll see 80psi & some many Lbs loads which is the max load your tire is supposed to carry @ that psi.So the only way to know how much to have for sure is to weigh your RV @ a Cat scales that will give you front & back axle weights.Because your correct pressure could be 70(if the front end weighs less than what's posted on the tire),over inflated tires wear more in the center & will ride rougher than a properly inflated tire for the weight on the axle.
HTH

[twinboat]

I use 80 in the rear but 65 in the fronts. It takes some of the harshness out of the expansion joints on the highway.

Besides, Ford went thru the trouble to find the right pressure, I use it.

Your front axle and suspension is only designed for so much weight.

It just so happens to be the load carriying capacity of your tires at 65 lbs.
If you weigh the front and need more then 65 lbs, you need to remove weight, not add air.

When I got new tires they filled them all to 80, it's just what they do.

[Traxless]

Originally Posted by sewmun

So the only way to know how much to have for sure is to weigh your RV @ a Cat scales that will give you front & back axle weights.Because your correct pressure could be 70 (if the front end weighs less than what's posted on the tire), over inflated tires wear more in the center & will ride rougher than a properly inflated tire for the weight on the axle.
HTH

+1

P.S. Take a look at the tire pressure chart on the Michelin Tire website. It supports the above guidance.

[Beabop]

Weigh the unit fully loaded then go by the tire makers chart not to exceed max on tire.. We had a 32 ft Ford MH that if you went by the card on the door, rode like a hay wagon. We have weighed all our units, am anxious to see what this lil class C takes.

[rvten]

The harder the tires. The harder the ride. For my MH weight. 70 FRT 80 Rear.