Goodyear Marathon Failures

[Silvertwinkie]

I thought using 10ply was a bad idea....not saying I know for sure, but thought I read that here.....FWIW....

Also, my Discount Tire place doesn't carry Maxxis!

[Al - K4GLU]

Before I put the 10 ply E load range tires on I called Airstream. The reason for my call was to find out if the aluminum rims could take the additional pressure since you can run the E up to 80 pounds - I run 70 in mine. I told the person I talked to what I was planning and he did not say it was a bad idea - but again I didn't specifically ask that question. The aluminum wheels by the way are good for up to 90 pounds pressure.

[Pahaska]

Originally Posted by Al - K4GLU

Before I put the 10 ply E load range tires on I called Airstream. The reason for my call was to find out if the aluminum rims could take the additional pressure since you can run the E up to 80 pounds - I run 70 in mine. I told the person I talked to what I was planning and he did not say it was a bad idea - but again I didn't specifically ask that question. The aluminum wheels by the way are good for up to 90 pounds pressure.

I have 65# in my Maxxis and I do not plan to exceed that pressure. Given the weight of my trailer, I would not even need to have as much as 65#, but I was told by Discount Tire's Regional Rep that I should always run the Marathons at max pressure, especially in the Texas heat.

[ljmiii]

Originally Posted by Silvertwinkie

I thought using 10ply was a bad idea....not saying I know for sure, but thought I read that here.....FWIW....

Andy (aka Inland RV) has advised against using 10ply - but I'm not sure if he is against them in general or against getting them and then inflating them up to 80 PSI (thus cracking your D rated wheels).

See post #4 in:

http://www.airforums.com/forum...tml#post258089

and also post #8 in:

http://www.airforums.com/forum...tml#post325688

enjoy,
leo

[hiker]

I can understand why putting 80# of pressure in a rim that was designed to handle only 70# may cause problems, especially with the valve stem. But don't understand why going from an 8ply to a 10ply tire would. Anyone know why?

[TomW]

Mike,

If you are the only one that fills your tires, I do not think there would be a problem because YOU know the rim & valve stem are not rated for the tire's potential pressure. The problem would be for people that go to the tire store and ask for 10 ply tires and don't check the pressure after installation.

Since the tire store would probably inflate the tires to the pressure listed on the tire wall, there would be a problem.

Tom

[lewster]

IIRC, the debate on the 10 ply tires centered around stiffer sidewalls producing a harsher ride and transmitting an excessive amount of shock and vibration into the trailer.......possibly shaking the daylights out of the beast.

I've been investigating 16" rims for my 19CCD with LT225/75R16 Michelins , as I am not comfortable with the Marathons and their 65mph speed rating. I tow 8-10,000 miles a year, mostly out West and need a higher rated tire, especially with a single axel!!

I am now leaning toward the 10 ply Maxxis in 15" to preserve the integrity of the free space in the wheel well. I'll report back when I make the transition.

Thanks for the great info on this thread!!!

[Pahaska]

Originally Posted by lewster

IIRC, the debate on the 10 ply tires centered around stiffer sidewalls producing a harsher ride and transmitting an excessive amount of shock and vibration into the trailer.......possibly shaking the daylights out of the beast.

When inflated to 65#, I believe that the increased 10ply sidewall stiffness is way down in the noise when supporting about 2000# of trailer.

By putting my weight on an unmounted tire at the dealer, I couldn't detect a great enough difference in stiffness over my 8ply Marathons to affect a loaded trailer. The same argument could be used for those upgrading from 6ply to 8ply.

No one of my friends has detected excessive vibration after changing to 10ply tires.

[TomW]

Originally Posted by Pahaska

... By putting my weight on an unmounted tire at the dealer, ...

Hmm, I wonder how many plies this fella has?





Tom

[ticki2]

Originally Posted by Al - K4GLU

Maxxis makes a "E" load range trailer tire so why in the world would you use LT? I have a 2007 20' Safari and have already removed my Marathons and replaced them with Maxxis ST225 75R15 10 ply E load range trailer tires. I had a Marathon failure on another make of trailer and friends of mine in NC had 2 Marathon failures. In all instances these were new or fairly new tires and had been pampered - pressure and tires themselves checked frequently. I still use the Marathons as spares - and I carry 2 spare tires for the trailer just in case.

What is the speed rating on the Maxxis E's

[Al - K4GLU]

Per the Maxxis website the speed rating for all of their trailer tires is 65. This suits me fine as my personal towing max speed is 65 - have no desire to go any faster. I just want the tread to stay on the tires and for the air to stay in them!

[hiker]

Originally Posted by TomW

Mike,

If you are the only one that fills your tires, I do not think there would be a problem because YOU know the rim & valve stem are not rated for the tire's potential pressure. The problem would be for people that go to the tire store and ask for 10 ply tires and don't check the pressure after installation.

Since the tire store would probably inflate the tires to the pressure listed on the tire wall, there would be a problem.

Tom

Isn't it safe practice to check cold tire pressure before every trip? If so, over inflation by a tire store wouldn't be a problem.

[TomW]

I did not say the tire store over-inflated the tires. I said they inflated them to what see as the specification on the sidewall.

Tires with more plies typically carry higher pressures.

But on the flip-side, many people do not check their tires themselves. Why would the local attendant know or care about the right pressure?

Tom

[lewster]

Originally Posted by hiker

Isn't it safe practice to check cold tire pressure before every trip? If so, over inflation by a tire store wouldn't be a problem.

I check tire pressures at the start of every day when I'm on the road, but that never gives you the whole story as to what is happening WHILE driving. The best way to keep an eye on the pressures while under way is with a tire pressure monitoring system. I use the Pressure Pro system. Easy to install and will warn you of any drop in tire pressure of 12.5%.....plenty of time to pull over and find the problem.

PM Overlander 68 for more information on this system. He's the resident pressure monitor expert!

[bhayden]

Originally Posted by lewster

I've been investigating 16" rims for my 19CCD with LT225/75R16 Michelins , as I am not comfortable with the Marathons and their 65mph speed rating. I tow 8-10,000 miles a year, mostly out West and need a higher rated tire, especially with a single axel!!

I am now leaning toward the 10 ply Maxxis in 15" to preserve the integrity of the free space in the wheel well. I'll report back when I make the transition.

So we must be talking about the radial Maxxis (aka Cheng Shin Rubber Co, remember the old Swallow motorcycle tires ). The 10 ply is a rating and does nothing but add confusion to the whole discussion. Maxxis also makes a Bias Ply ST tire and I noticed that even on those it's a 6PR or 8PR spec meaning "ply rating" and has nothing to do with the actual number of plys used in the construction.


http://www.maxxis.com/products/trailer/overview.asp

The Maxxis radials are undoubtedly a 2 ply construction like virtually every other radial tire. The ply rating is nothing more than a (bad) way of restating Load Range. The amount of sidewall flex will be way more in a radial than in bias ply. They're designed to flex. I'd bet dollars to doughnuts that even the lowest rated bias ply tires have a stiffer sidewall than the E rated radials.

Sidewall stiffness and ride "quality" don't coorespond as simply as has been put forth in this and other threads. Remember the GM slogan "Radially tuned suspension" and shocks that are labled similarly? At low speed radials were noted to produce a "harsh" ride or what more sporting drivers called "road feel". At highway speeds the radials lower rolling resistance is because of it's ability to absorb roadway imperfections and therefore produces a smoother ride.

In general a lower tire pressure will result in a tire that's able to deform and absorb bumps better. If the road is perfectly smooth then higher pressure will decrease rolling resistance. However, in the real world the deflection caused by higher pressure often results in a higher rolling resistance so it's almost always a compromise that's going to depend on the load, the road surface and the speed.

Just to make things a little more confusing you can't compare load ratings for an LT tire directly to those for an ST rating. The LT tires are derated (or the STs are overrated ) for several reasons. First the LT tires are for passenger carrying service and somehow they figure it's not as dangerous to suffer a blowout on a trailer that may exceed the weight of your tow vehicle . Second the LT tire is rated for use on a drive axle and a steering axle; both of which put more strain on a tire than simply following along (there's nothing in the spec for ST rating that covers backing your trailer). Finally, and it's a major consideration, the LT tires are load rated for a higher, sometimes significantly higher speed. If all tires followed the UTQG system it might be a little easier but there's still a lot of manufacturerer spec engineering and if people saw the UTQG rating for ST tires they probably wouldn't buy them

-Bernie

[Silvertwinkie]

So I'm basically back to square one then....and I guess go with a new set of Marathons? This is like that one joke, you ask one question and get a thousand different answers...all of which sound right on the money....

[2airishuman]

Originally Posted by bhayden

... if people saw the UTQG rating for ST tires they probably wouldn't buy them -Bernie

i bernie...

very good post.

and i agree with every thought except this last one.

i REALLY would like to see the UTQG rating for st tires.

virtually everyone mis understands the current st speed 'rating' and mis compares it to passenger tire 'speed' ratings....

cheers
2air'

[TomW]

Originally Posted by bhayden

The Maxxis radials are undoubtedly a 2 ply construction like virtually every other radial tire.

I take it you are speculating like the rest of us are? It does not appear from your post that you have ever owned any Maxxis tires.

(... aka Cheng Shin Rubber Co, ...

Was the fact that these tires may be made overseas supposed to surprise anyone? From what I have read, Marathons are not made in the U.S. either.

I don't necessarily disagree with anything you said in your post, but I missed any point you may have been trying to make. Were you trying to make a point?

Tom

[Blu_Hwy_Lady]

Google Marathon Tire Failures. Read the long list of complaints from owners of SOBs on Eopinions. It has nothing to do with proper inflation. The Marathons are crappy tires and they have been for a long time. Here's an interesting statement I found about a class action suit that seems to have disappeared:

A class-action suit has been filed in Massachusetts accusing Goodyear of
launching a silent recall. The lawsuit claims the tire maker failed to warn
consumers that its 15-inch Marathon tires are unsafe and unsuitable for
campers. (The Associated Press State & Local Wire, November 7, 2000)

I found lots of other postings on other RV message boards that relate tales of woe related to the Marathons. So, no more ruminating over proper tire inflation and weight. The tires are junk no matter how they're inflated.

[ticki2]

virtually everyone mis understands the current st speed 'rating' and mis compares it to passenger tire 'speed' ratings....

cheers
2air'[/quote]

Even the people who wrote it , the statement contradicts itself.