Tire air pressure question

[allbrand1999]

I have a 2007 holiday rambler imperial 42 foot diesel pusher with a tag axle tire size is 295/80 R 22.5
Load range (H) I have six Goodyears on the back and two Michelin's on the front.
On the tires it says 120 psi max load I was wondering what most people run for tire pressure 120 PSI seems very high to me looking for opinions thank you so much.

[Mr_D]

What does the Federal weight sticker show? That is the minimum pressure required to support the maximum rating of your vehicle and will be too high in most cases. But thats a safe starting point till you can get it weighed, and use the tire charts to reduce the pressure.

[FastEagle]

“The recommended inflation pressures for RV tires are indicated on the vehicle tire placard, certification label, or in the owner's manual. Never set tire inflation pressures below the recommended inflation pressure found on the vehicle tire placard, certification label or owner's manual.”

That’s the lead statement about proper RV tire inflation in chapter four of the reference listed below. It’s a must read for “do-it-yourselfers”.

http://www.mcgeecompany.com/wp-conte...ete-manual.pdf

[allbrand1999]

Where is the federal sticker are we talking about what it says on the tire or what it says for the weight of the Motorhome like I said earlier on the tire itself it says maximum inflation 120 psi

[JSandDS]

Usually somewhere on the wall next to the driver's seat, could be low.
It should show pressures for each axle, usually different for each.

Sent from my XT1650 using iRV2 - RV Forum mobile app

[Gdawgs]

Originally Posted by allbrand1999

I have a 2007 holiday rambler imperial 42 foot diesel pusher with a tag axle tire size is 295/80 R 22.5
Load range (H) I have six Goodyears on the back and two Michelin's on the front.
On the tires it says 120 psi max load I was wondering what most people run for tire pressure 120 PSI seems very high to me looking for opinions thank you so much.

We have similar weight coaches and the same tires. The placard behind the driver's seat says 100psi front and 85psi for drive and tag. I found the front to be to soft showing outer edge wear on the tires at 100psi. The drive and tag seem to be OK at 85psi. I increased the front tires to 105psi and am getting even wear across tread with no effect on ride quality.

[allbrand1999]

OK great thank you everyone I do know where the tag is that you're speaking of I believe it has the Vin number on it also kind of a hard place to see but I will look thank you again

[Jeff753]

I run at or above my axle rating. That way the axle will be the weakest link?

[TomAndPeg]

I went through quite a learning process on this very important safety topic.

Once I thought I had my act together, I had a confirming conversation with Monaco Support (sage advisors), then followed these steps for setting the optimal tire pressure on my Dynasty:

1. Obtained a manufacturer's tire inflation chart for my particular tires (online).
2. Measured the loaded weight on all three axles (Cat Scale -- a novel experience).
3. By adjusting the tag axle and re-weighing, I made sure each axle weighed within a balanced tolerance of the manufacturer's stated capacity. I targeted a 75-80% weight/capacity ratio per axle (you'll find an axle weight capacity chart in your owner's manual or brochure).
4. Reset the tire inflation per axle within tolerance of each axle's final weight loading (direct any specific questions about this to the tire manufacturer).

A special note about your tag axle: it was set by the factory at an optimal down pressure for your specific coach, so before you start making any tag adjustments, obtain your initial axle weight distribution; you might discover the current tag axle pressure setting is still optimal. If it is, don't fiddle with it. If it isn't, adjust and weigh and repeat until weight distribution is back in a good range. (The tag axle adjustment process is detailed in your owner's manual.)

I have the same size tires as you, and my final PSI settings are 95/85/75 (F/D/T), which is nowhere near what I naively expected when I got started. As a result of these adjustments, the coach handles even better, drives much smoother, and my mileage had improved by about 5%.

Knowledge is the key, so keep asking questions.

Good luck!

[Tireman9]

I have numerous posts in my RV Tire Blog on the how to set the tire pressure on your RV and the why you should not simply use the inflation another RV owner uses.

The Tire placard is based on the idea that you will be running exactly at the axle GAWR. No more and no less. The numbers are set based on federal regulation to ensure that the tires are inflated with sufficient air pressure to support 100% of the GAWR.
These regulations are based on a LOT of assumptions.

You can follow them or you can be a more informed and proactive owner when it comes to tires.

Get thee to a scale and learn the facts of what your RV actually weighs (see posts on 4 corner weights to do the best job possible)


Yes Fast Eagle and I have agreed to disagree.

[Mr_D]

Originally Posted by FastEagle

“The recommended inflation pressures for RV tires are indicated on the vehicle tire placard, certification label, or in the owner's manual. Never set tire inflation pressures below the recommended inflation pressure found on the vehicle tire placard, certification label or owner's manual.”

That’s the lead statement about proper RV tire inflation in chapter four of the reference listed below. It’s a must read for “do-it-yourselfers”.

http://www.mcgeecompany.com/wp-conte...ete-manual.pdf

This is what my owners manual states also. So thats what I do. My front axle is rated for 20,000#'s and weighed 18,030 when the late DW was seated. So I'm well under the max weight. But when I stop and check the tire temp it's anazing how much cooler they are than what the tires on my last rig ran using the lower pressur that the charts allow.
Everybody has choices, I choose to follow the owners manual with this MH.

[allbrand1999]

Thank you everybody very much