RV Manufacturer versus Tire Company air pressure settings

kaydeejay wrote:

More To See wrote:
Those plaques the RV manufactures put on vehicles spelling out tire pressures are absolutely dangerous. But I think they are required by the feds.

With not a clue in the world of what tires you are running on your rig how could they possibly be able to tell you what air pressures to run with.

How many rigs are out there right now running down the road with severely under inflated tires because somebody use those stupid plaque recommendations?

Perhaps a little work with a hammer and chisel might save some lives.

I call BS on these statements.

I suggest you retract them as what you are saying is incorrect, misleading and potentially dangerous!

The tire placard pressures stated by the Manufacturer are those required for the tires to run with axle loads at their maximum. Tires at the pressures on that placard are NOT "severely underinflated" unless the vehicle is also overloaded. You are right in that "they are required by the Feds". The Feds also require that the pressures are as I have stated.

Turning your statement around, the tire manufacturers have no idea what weight the tires will be carrying, so how can they know what pressure you should run?
(They provide load/inflation charts for that purpose. The numbers on the tire label will be very close to those chart numbers for the weight being carried)

(In the interests of full disclosure, those labels used to be part of my job at one of the "Big 3" so I do know what I am talking about!)

I stand by my posting.

Right now my door plate recommends 65 psi front and rear but I have to run 95 psi front and rear per Bridgestone for my weight. And I'm not overloaded.

And in every past post I can remember from others they see the exact same thing. A very low recommendation of what tire pressure to run.

May I just refer back to the OP today. How far down the road would he get running those door post pressures?

On edit: assuming this isn't a brand new rig straight out of the factory.

More To See wrote:
Those plaques the RV manufactures put on vehicles spelling out tire pressures are absolutely dangerous. But I think they are required by the feds.

With not a clue in the world of what tires you are running on your rig how could they possibly be able to tell you what air pressures to run with.

How many rigs are out there right now running down the road with severely under inflated tires because somebody use those stupid plaque recommendations?

Perhaps a little work with a hammer and chisel might save some lives.

This is one of the most ridiculous replies I have ever read here! Winnebago knows exactly what tires (load range) they are installing and the maximum loads per axle the coach is designed to carry. They use these figures to determine the tire pressures on the plackard.

Please know what you are talking about if you wish to be helpful in the future.

Jackie Treehorn wrote:
Winnebago suggests 70 psi for my front tires and 75 psi for the dual tires in the rear. The tire company has the fronts rated at 110 and the rears at 90. Which is the right way to air the rig up?

are you using the tire mfg load inflation table to come up with 110 and 90 or by what is stamped on the tires? the proper way is to use the minimum inflation for the load being carried. load the RV as you normally would, weigh the front and rear axles separately...at least get separate weights...and inflate as per the mfg chart.

Here's a web site that has some good info and the links page has links to tire manufacturers and chassis mfr's as well.

RV Weigh-Tire Pressure

Thank you all for the spirited discussion on psi! I'll opt to take a trip this weekend to Death Valley with the pressure down to the Winnebago specified levels and then adjust as necessary from there. All the advice is appreciated!

Thank you Keith!

My gasser, with Goodyear 19.5" tires: I had the same confusion: I ran 80 psi (the sidewall said Max 85)...then I weighed the rig...front/back, recorded the weights and called Goodyear.
Lady on the phone told me that I could use LESS pressure all around, but if I was happy with 80 all around (all 6) no problem.

More To See wrote:
Those plaques the RV manufactures put on vehicles spelling out tire pressures are absolutely dangerous. But I think they are required by the feds.

With not a clue in the world of what tires you are running on your rig how could they possibly be able to tell you what air pressures to run with.

How many rigs are out there right now running down the road with severely under inflated tires because somebody use those stupid plaque recommendations?

Perhaps a little work with a hammer and chisel might save some lives.

I call BS on these statements.

I suggest you retract them as what you are saying is incorrect, misleading and potentially dangerous!

The tire placard pressures stated by the Manufacturer are those required for the tires to run with axle loads at their maximum. Tires at the pressures on that placard are NOT "severely underinflated" unless the vehicle is also overloaded. You are right in that "they are required by the Feds". The Feds also require that the pressures are as I have stated.

Turning your statement around, the tire manufacturers have no idea what weight the tires will be carrying, so how can they know what pressure you should run?
(They provide load/inflation charts for that purpose. The numbers on the tire label will be very close to those chart numbers for the weight being carried)

(In the interests of full disclosure, those labels used to be part of my job at one of the "Big 3" so I do know what I am talking about!)

Those plaques the RV manufactures put on vehicles spelling out tire pressures are absolutely dangerous. But I think they are required by the feds.

With not a clue in the world of what tires you are running on your rig how could they possibly be able to tell you what air pressures to run with.

How many rigs are out there right now running down the road with severely under inflated tires because somebody use those stupid plaque recommendations?

Perhaps a little work with a hammer and chisel might save some lives.

Jackie Treehorn wrote:
Winnebago suggests 70 psi for my front tires and 75 psi for the dual tires in the rear. The tire company has the fronts rated at 110 and the rears at 90. Which is the right way to air the rig up?

The 70/75 from Winnebago is based on the originally installed tires and with your rig weighing the maximum amount that the axles are rated for.

The 110/90 is the maximum you should inflate the tire to. On the tire sidewall it will tell you that the tire will hold xxxx pounds at this pressure.

You would be perfectly safe at either of these inflation points, but your ride would probably be a bit harsh, especially using the tire sidewall pressures.

Instead go to the tire manufacturers web site and search for an inflation chart. Some of them only put this into the brochure for the tire, so you may have download that. A Google search will sometimes be faster than digging around the web site.

The chart from the tire manufacturer will tell you what the inflation pressure should be for a given weight on a tire. So, you have to get at least axle weights, like you would get at a truckstop, or better yet, corner weights. If you use axle weights, then divide that number by 2 to get the weight for a particular tire.

If your weight per tire is way down at the bottom of the chart, use the lowest inflation that they list to avoid going too low.