RV Tires vs. Truck Tires

[twalton@povn.com]

Something else I should mention is that I use 303 Aerospace protectant on my tires. It is not petroleum based and is SPF 40 for your stuff. http://www.303products.com/

[wmpbauer]

Which of the PSI sensor systems are recommended? Which to be avoided at all costs?

Do you install them for all 10 wheels?.......that seems the only way to do it if you're going to do it at all......

[mlwoodward]

We recently purchased an '06 Newmar Mountain Aire. The tires are beginning to show some checking. The tires are Michelins that were made in the 3005 so we're going to replace them in the next few weeks before we take another a trip that will probably last 6+ weeks. We were going to go with Michelins but after reading what you all have said will probably go with Toyo. Our RV dealer is highly recommending the "Tryon". I only recall seeing it mentioned once in all of the replys ... will it do what its manufacturer (and our dealer) market it to do or is this marketing hype??? Does anyone have any experience or knowledge regarding the Tyron??

[wolfe10]

We recently purchased an '06 Newmar Mountain Aire. The tires are beginning to show some checking. The tires are Michelins that were made in the 3005 so we're going to replace them in the next few weeks before we take another a trip that will probably last 6+ weeks. We were going to go with Michelins but after reading what you all have said will probably go with Toyo. Our RV dealer is highly recommending the "Tryon". I only recall seeing it mentioned once in all of the replys ... will it do what its manufacturer (and our dealer) market it to do or is this marketing hype??? Does anyone have any experience or knowledge regarding the Tyron??

Welcome to the FMCA Forum.

Not familiar with Tyron brand tires, and Googling came up with nothing. Or is Tryon your RV dealer's nickname for Toyo??????.

And, what size tire do you need?

[TONYLACEY]

Gentlemen,

After reviewing some of your post I plead with you please do your research before you spend a dime on anything that has to do with a tire. I am a tire dealer Georgia and have developed a Love for the RV/Coach business I attended the FMCA rally in Perry and plan to attend more. All that being said, there are a TON of aftermarket products on the market that are pitched at coach owners by scare tactics etc. I am a Michelin Dealer and do recommend the Michelin tire for your coach and can answer any questions that you may have regarding why.

But from a guy that will sell you anything that you want, know this: the three most important things that have to do with your tires are air pressure, Air Pressure, AIR PRESSURE!!!

Regardless of which tire that you have or decide to go with if you maintain the air pressure in the tire based on the tire manufactures specifications for the load (NOT MAX PSI) which is what is on the sidewall of the tire, it will increase your overall performance and your overall satisfaction.

Lastly if you are planning on purchasing tires within the next two weeks, you may want to stand by for a Very Special announcement!

[tmoning]

Lastly if you are planning on purchasing tires within the next two weeks, you may want to stand by for a Very Special announcement!

The announcement to which Tony is referring is the new FMCA Michelin Advantage Program, which allows FMCA members to claim substantial discounts on Michelin RV tires from Micheline tire dealers. Here is the link for more info:

FMCA Michelin Advantage Program

[tireman9]

Let me correct some of the misunderstandings out there about the use of Nitrogen in tires.

Let's start by looking at the options for inflating tires:

1. Nitrogen

2. DRY air

3. "Normal" WET air

There is virtually no difference between Nitrogen and dry air when it comes to PSI change with temperature change. Both follow Boyles law (Physics is physics, irrespective of what sales literature says).

Now, wet air (like from any air compressor without a dryer) is a very different matter. And most air from those convenience store coin op compressors is WET. Water is clearly not an "ideal gas" and PSI changes more with temperature than for a gas.

Nitrogen molecules average very slightly larger than "air" (which is 78% Nitrogen anyway), so leakage will be slightly less.

Nitrogen is not reactive so filling a tire with it will be slightly better for the tire and rim than air which has Oxygen which will deteriorate the tire. But most tire oxidation/cracking occurs from the outside of the tire. Clearly, wet air is much worse.

My opionion-- Nitrogen is slightly better than dry air for your RV tires. Dry air or Nitrogen are both a LOT better than regular "wet" air from those 7-11 coin operated compressors.

Whether Nitrogen is worth it is up to your budget and what you will have to pay. If you are a welder and have it in your shop, great idea.

Brett Wolfe

I agree with Brett and have more extensive info on Nitrogen in my Blog

[tireman9]

A general comment on Truck vs RV tires from a Tire Development Engineer.

If we stay with the same size and Load Range, some tires may have some extra anti-ozone chemicals built into the sidewall but I am not aware of any meaningful structural difference other than advertised differences such as tread depth and pattern, both of which can affect ride & handling as well as long term durability and fuel economy.

If you read the materials listed on the sidewall you will see that most tires for Class-A have one body ply of steel. The tread area may have three or four steel belts but usually the difference here is also related to expected usage which also involved different tread depth and tread pattern.

Given that most tires on RV "age out" rather than "wear out" I would probably shop around for the tire with the shallowest tread as that would in all likelihood also give best fuel economy as well as be of lower cost with the possibility of better ride too.

When you are inflating a tire to 100psi there is not too big of a difference in ride between tires when you do controlled back to back tire evaluations which in the real world probably no one here has ever done unless they have worked as a tire development engineer for one of the big tire manufacturers or a big car manufacturer. This type of testing involves running at identical loads & speeds over a specific set of road conditions with no traffic to hinder the test.

When you get to the fine points there is no radio playing and the AC is off and all windows are closed so noise is not masked either. While an experienced & trained evaluation engineer might be able to feel a minor difference, most times the difference is well below the sensory threshold of 98% of every day drivers.

Switching from shallow tread 6 year old tires to new tires is apples to oranges comparison as tread depth alone will vastly overshadow any possible construction difference.

[tinkertim]

RV tires are made to reduce squirming et , some are 14 ply. I hauled winter weights on a log truck for years with 10 ply. Only time I got squirming was when the frost was coming out of the highway just base it on how safe you want to feel, I feel the suspension should give the smooth ride not the tire )

[tinkertim]

Good point with the ozone protection. That probably was a feature because of the sitting motor-homes do and hot areas they are parked in. )

[Smoker]

I have a question on air tire pressure. I have Michelin XRV 255 80 R 22.5. I read my chart that at 105 psi I can carry a total of 29,040 lbs. I'm I reading this right ? (9370 lbs each on the duals and 5150 lbs on the singles ?)

Also what is meant by the cold air pressure? Is this when I should be checking and adding? to ensure I have a true 105 psi ?

Thanks...Ron

[wolfe10]

Ron,

Yes, if your front axle weights are 5150 on the heavier wheel position and your rear axle weights are 9370 on the heavier side, then indeed, 105 would be the correct pressure. But, it is rare that pressures work out the same from one axle to the other. Each axle is considered separately, with the heavier wheel position determining where to go to the chart-- all tires on that axle getting the PSI based on the heavier wheel position.

And "cold" is not a particular temperature, but " before driving at whatever the ambient temperature is. So in the winter in the morning, it may be 32 degrees F and in the summer 80 degrees F. The PSI would be adjusted to the same specified for your loads.

Brett

[desertdeals69]

When I went from 19.5 to 22.5 about 10 years ago I bought Toyos because they cost less than Michelins. I paid less than $180 each for 245/75x22.5. I was told Michelins would ride smoother so about 2 years ago I tried them and they do ride much smoother. I guess the sidewalls are more flexible. There is a difference between a truck tire and an RV tire in some sizes. The Michelins are 235/80x22.5 with the same diameter.

[tireman9]

I have a question on air tire pressure. I have Michelin XRV 255 80 R 22.5. I read my chart that at 105 psi I can carry a total of 29,040 lbs. I'm I reading this right ? (9370 lbs each on the duals and 5150 lbs on the singles ?)

Also what is meant by the cold air pressure? Is this when I should be checking and adding? to ensure I have a true 105 psi ?

Thanks...Ron

My suggestion on tire pressure for motorized RVs can be found HERE.

I think there may be some confusion on the Michelin loads. The 255/80R22.5 XRV or XZE at 105 psi cold inflation is rated for 5,150 # each in single (front) position.

The load rating for each tire is 4,685# each tire when used in dual fitment.

Some tire charts give just the load capacity for each tire while Michelin gives the load capacity for each end of an axle.

[mblwhdqtrs]

My Motorhome is 8 years old. Iam considering Firestone FS560, Sumitomo ST 727, and at a much greater cost, Goodyear G670RV. We are retired and are starting to travel off and on about 3 to 4 times a year @ 4000 miles a trip with extended stays from time to time. My hope is to keep the rig for another 3 to 5 years. Thanks for anyone's input or experience on this manner, gpottinger , mblwhdqtrs