New Tires??

[rhagfo]

Originally Posted by Jim & Kay

IMHO, replacing rv tires every four years is a very smart move, But towing an rv at 75 mph is Very DUMB !!!!!

Originally Posted by Festus2

Jim:
No argument from me on that!

I agree with both of you, while I have no issue with getting up to speed going 60 pulling 11+K of trailer your chances of recovering from an emergency move go way down over 60 and get pretty slim at 70+.
Watched some idiot tailgating a working snow plow over Oregon 6 to the coast at about 45 mph, he was about 50 to 60 feet off the plows bumper on snow he was pulling a out a 35' toy hauler just pushing the limits in my book!

[CWtheMan]

Originally Posted by seahunter

Regarding speed safety:

•All "ST" tires have a maximum speed rating of 65 mph.
•As heat builds up, the tire's structure starts to disintegrate and weaken.
•The load carrying capacity gradually decreases as the heat and stresses generated by higher speed increases.

Just a note here: Carlisle only recommends 60 MPH for their trailer tires.

CW

[ls1mike]

I think you only really hear about the bad things on the internet. I had Carlises on the old trailer for 4 years and 10,000 miles. People said they would blow up and wear out. I kept them air up end checked the temps with an infrared temp checker from time to time while on the road towed at 60 and under. I never had one problem.

Stuff happens but take care of the tires properly and you should have no problems.

[azlee56]

Now that I am being brave. I looked at our Montana tires and said WOW. I never hear of E tires before, so I had to go ask the guys here what is E tires? So this guy told me. Then there was some other tire and I said "what the heck is that?". One day the BF and I were out in the yard so I was reading our Montana tires and I said. hmmm. What are G tires that need 110 lbs of pressure? He said WHAT? I said that is what it says, come look. He had them at 85. I said again what is G tires? So I had to go look. I guess they are heavy duty. Then I looked at the truck and said HEY they are E tires.

What a lesson I am getting here.

[azlee56]

wow I am a senior member (which I am not)!!!

[seahunter]

Originally Posted by azlee56

Now that I am being brave. I looked at our Montana tires and said WOW. I never hear of E tires before, so I had to go ask the guys here what is E tires? So this guy told me. Then there was some other tire and I said "what the heck is that?". One day the BF and I were out in the yard so I was reading our Montana tires and I said. hmmm. What are G tires that need 110 lbs of pressure? He said WHAT? I said that is what it says, come look. He had them at 85. I said again what is G tires? So I had to go look. I guess they are heavy duty. Then I looked at the truck and said HEY they are E tires.

What a lesson I am getting here.

Another thing to realize too is just because that G-rated tire says 110 psi, does not mean you need to be running it at 110 psi. You need to look at the actual load you are running. If you're not running at maximum load, you can run them at 90 or whatever matches the load guides. Otherwise you will just have a rougher ride and keep the higher pressure unneccesarily. I am getting the Goodyear G614 tires which are the G-rated tire and will probably be running at 90-95.

[azlee56]

thanks. I will tell the BF that, but I have a question in the AZ hot weather it is better to do less cause they get hot?

When he first put pressure in the tire, he did the stand back and look and that is where he came up with 85 pressure (he drove semi's) when I read 110 psi and said don't know and he said that is what it says so ok, he really was surprised. In AZ at 100+ degrees they do get hot. The others that saw my weight might add on here.

[seahunter]

Originally Posted by azlee56

thanks. I will tell the BF that, but I have a question in the AZ hot weather it is better to do less cause they get hot?

When he first put pressure in the tire, he did the stand back and look and that is where he came up with 85 pressure (he drove semi's) when I read 110 psi and said don't know and he said that is what it says so ok, he really was surprised. In AZ at 100+ degrees they do get hot. The others that saw my weight might add on here.

As you probably already know, always check when they are "cold", meaning they have not been driven on yet. Actually if you have them lower in psi, it will cause more friction and raise the tire temperature. I do not live in an extremely hot climate so I'll let others chime in on this more. One other thing to consider is possibly a tire pressure monitoring system (TPMS) - one tha not only monitors pressure, but also temperature of each tire...

[azlee56]

the tire monitoring system will probably be his xmas present...or I should say our xmas present.

[CWtheMan]

RV trailer tire pressures for Original Equipment (OE) tires need to be kept at the recommended pressure (s) found on the tire placard/certification label or in the owner’s manual. There is zero justification for using less pressure than what has been recommended by the vehicle manufacturer with the exception of special circumstances found in the owners manual.

CW

[seahunter]

Originally Posted by CWtheMan

RV trailer tire pressures for Original Equipment (OE) tires need to be kept at the recommended pressure (s) found on the tire placard/certification label or in the owner’s manual. There is zero justification for using less pressure than what has been recommended by the vehicle manufacturer with the exception of special circumstances found in the owners manual.

CW

CW,

I respectfully disagree. That is what a "Load Inflation Table" is for. In my case I do not need to run my tires at 110 psi if I am not fully loaded. In fact, if I run them at full load (3,750 X 4 = 15,000 pounds) I would exceed my particular axle weight rating.

I submit this link:

http://www.goodyearrvtires.com/tire-selector.aspx

and then hit "Download Load Inflation Table"

to show the various tire load limits based on psi.

[Festus2]

Goodyear also has another link on the same site page in addition to the table mentioned above. Click on "RV Tire and Care Guide" and it explains there that the "tire inflation should be adjusted to the tire carrying the heaviest load". It also goes on to say that you need to weigh your set-up to find out what the load on each axle will be and then adjust your pressure accordingly within the load limits of the tire.
Someone who has a GoodyearG614 for example, as does seahunter and geo, can adjust their tire pressure to less than 110psi if it results in a "softer" ride. The Tire Load Inflation table would indicate what the recommended pressure would be for the axle load of their RV's.
This Goodyear guide makes for excellent and informative reading.

[jsmith948]

Hello SeaHunter,

Well, I get all that, but; how do you avoid the sidewall flex (and the heat build up) resulting from running the tire under-inflated? In other words, if I am loaded up for a long trip, I should be at 65psi, but if I drain the water and remove all of our gear (say to go to the dealer for service) then I should run less air pressure?
When I drove OTR (2.5 million miles) I ran 105 psi in my trailer tires regardless of how heavy the load was. I think there might be more than one way to read the tables to which you refer.
No argument intended - just IMHO

[azlee56]

the tires that are on the montana are different then what is on the label. The label says type E and 85 lbs, but the tires on it are type G and the tire says 110 psi. I read that type G tires are 14 ply. Not sure I read the right thing but I was surprised. Both are 16 inch though.

[seahunter]

Originally Posted by jsmith948

Hello SeaHunter,

Well, I get all that, but; how do you avoid the sidewall flex (and the heat build up) resulting from running the tire under-inflated? In other words, if I am loaded up for a long trip, I should be at 65psi, but if I drain the water and remove all of our gear (say to go to the dealer for service) then I should run less air pressure?
When I drove OTR (2.5 million miles) I ran 105 psi in my trailer tires regardless of how heavy the load was. I think there might be more than one way to read the tables to which you refer.
No argument intended - just IMHO

Hi Jack and Marty,

I guess the best way to look at it is more of a range of tire pressure built into the tire than actually being under-inflated. As per the Goodyear literature, the G614 has a "premium casing and mold shape design" and "solid, rounded shoulder ribs (which) increase rib stability".

Technically yes, anytime you adjust the load by a substantial amount, you would be able to adjust the tire pressure for the maximum quality ride. You can run any tire at full maximum all the time, it just may be that it is unnecessary air pressure for the given weight and just results in a harsher ride.

You're probably right on more than one way to look at it , and I'm not an expert by any means and learning all the time...

Take care.

[seahunter]

Originally Posted by azlee56

the tires that are on the montana are different then what is on the label. The label says type E and 85 lbs, but the tires on it are type G and the tire says 110 psi. I read that type G tires are 14 ply. Not sure I read the right thing but I was surprised. Both are 16 inch though.

Yes, E-rated are 10-ply and G-rated are 14 ply rated. Current Montanas that are not Big Skys, come with Goodyear Marathon E-rated tires. If they have the Big Sky package, they come with Goodyear G614s which are the G-rated tires. They just began allowing a stand-alone option of upgrading the tires on any Montana to the G614s which is what I was able to do. They are not cheap tires, but offer a lot of peace of mind especially with a not-so-great reputation of the Marathons amongst a lot of RVers. Not to get into a huge hornets nest, just stating fact, but the Marathons are not made in the U.S., and the G614s are made in the U.S.

[azlee56]

OH! thanks for that explanation and now I know our little ark has the Big Sky package and 10 anniversary stuff.

[seahunter]

Originally Posted by azlee56

OH! thanks for that explanation and now I know our little ark has the Big Sky package and 10 anniversary stuff.

I see yours is a 2008 - is it new to you? It should say "Big Sky" on it if it is a Big Sky. If you bought it used, they may have just replaced the tires at some point with the G-rated tires.

[azlee56]

It was used when we got it, some military high up guy had it and traded it in for a $100,000 motorhome. It was a friend of the salesman. No it doesn't say big sky on it. 3500RL Montana. I do know it is the anniversary addition and had all kinds of upgrades to it.

[Outbackmel]

8000 miles and look and ride as new. Recent 6000 mile trip, never an issue.
If I 20, 10 & I 40 are not a good durability test, what the heck is?
Second only to PA pothole turnpike.

Check pressure and lug nuts and pull that sucker.