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Old 06-11-2019, 12:10 PM   #31
CWtheMan
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Everyone is shouting BUY USA tires. Goodyear built ST tires in China that became China Bombs. China is now building ST tires in NC. What will they become?
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Old 06-11-2019, 02:04 PM   #32
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Everyone is shouting BUY USA tires. Goodyear built ST tires in China that became China Bombs. China is now building ST tires in NC. What will they become?
Better tires??
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Old 06-11-2019, 03:53 PM   #33
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I looked at this from Reddit on my iPhone and thought "Looks just like some of us from the Keystone forum (or insert your favorite forum). Tires seem to come under this area sometimes. I don't know enough about the technical end of tire building to join in that never-ending conversation, but I do know about my 'Chine-bomb Trailer Kings' and the 9K damage that Geico shelled out. Tires that were perfectly cared for, TPMS, infrared thermometer readings at every stop. And I do know about the stories from countless other members with the same ending. Chris and a number of other posters have the right idea; either tell the dealer that you won't accept those tires or bite the bullet and have new tires installed right off the lot. JMO, YMMV
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Old 06-11-2019, 04:23 PM   #34
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Loadstars are on my trailer currently. Where do they stand? Regardless they are only load range C, I don't think that's enough.
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Old 06-11-2019, 04:52 PM   #35
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OK Here is kind of my overview of tires.
1. The basic format for load capacity is Size (air volume) x PSI x K
2. The "K" is supposed to be a factor that relates to the tire service. If a tire is normally run with a 25% Reserve Load (to account for occasional low inflation or high load) on the improved highway for 3 to 5 years, you might have a high K factor like 1.1. On the other hand, if a significant portion of the population of tires will be operated under-inflated or overloaded and you want 10 years life then the k should be a lower value like maybe .80. But what happens when the vehicle design imparts excess belt stress sometimes 24% higher than seen on normal motor vehicles? The K factor should be reduced significantly. Maybe even 24% to 0.65

2. The RV industry lobbied long and hard to not upgrade the durability improvements that were placed on P and LT tires in 2002. Why? They didn't want to spend more on tires. DO they care more about their bottom line than you having no tire problems? What do you think?

3. The ST load formula was based on a MAX speed of 65 with normal highway speed of 55.
4. Given that the RV trailer travels at the same speed as the tow vehicle, why would you expect people to slow down when the strong engine can easily pull at 80 mph?
5. What is the difference between an LT tire and an ST tire today? They both travel at the same speed on the same roads. The LT only needs to last 4 to 5 years but the RV tire does not wear out till 10 years + in many cases.
6. Under what logic would you expect a tire with the letters "ST" on the sidewall to be able to carry 20% more load than a tire with the letters LT on the sidewall. The physics of Size x PSI still holds but now the operational speed of the LT and ST are the same.
7 If there were some magic rubber that allowed a company to make tires that can carry 20% more load (the difference between LT and ST) Why wouldn't the company put that "Super" compound in their premium LT tire line?

8 Only a few tire companies make ST tires. Ever wonder why? Do you think it's possible that they do not want to make tires that they can be fairly confident will not live long enough to wear out before they fatigue? Why would you make a product where a majority of the users abuse your product? Even if you do not warranty the product for more than a year it certainly doesn't make people feel confident in your brand, does it?
If I were King I would do away with ST type tires and require a 20% load margin on LT type tires in RV trailer application and require TPMS on all RVs.


But I'm not King so all I can do is offer suggestions to help people get better tire life.
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Old 06-11-2019, 05:51 PM   #36
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Originally Posted by Tireman9 View Post
OK Here is kind of my overview of tires.
1. The basic format for load capacity is Size (air volume) x PSI x K
2. The "K" is supposed to be a factor that relates to the tire service. If a tire is normally run with a 25% Reserve Load (to account for occasional low inflation or high load) on the improved highway for 3 to 5 years, you might have a high K factor like 1.1. On the other hand, if a significant portion of the population of tires will be operated under-inflated or overloaded and you want 10 years life then the k should be a lower value like maybe .80. But what happens when the vehicle design imparts excess belt stress sometimes 24% higher than seen on normal motor vehicles? The K factor should be reduced significantly. Maybe even 24% to 0.65

2. The RV industry lobbied long and hard to not upgrade the durability improvements that were placed on P and LT tires in 2002. Why? They didn't want to spend more on tires. DO they care more about their bottom line than you having no tire problems? What do you think?

3. The ST load formula was based on a MAX speed of 65 with normal highway speed of 55.
4. Given that the RV trailer travels at the same speed as the tow vehicle, why would you expect people to slow down when the strong engine can easily pull at 80 mph?
5. What is the difference between an LT tire and an ST tire today? They both travel at the same speed on the same roads. The LT only needs to last 4 to 5 years but the RV tire does not wear out till 10 years + in many cases.
6. Under what logic would you expect a tire with the letters "ST" on the sidewall to be able to carry 20% more load than a tire with the letters LT on the sidewall. The physics of Size x PSI still holds but now the operational speed of the LT and ST are the same.
7 If there were some magic rubber that allowed a company to make tires that can carry 20% more load (the difference between LT and ST) Why wouldn't the company put that "Super" compound in their premium LT tire line?

8 Only a few tire companies make ST tires. Ever wonder why? Do you think it's possible that they do not want to make tires that they can be fairly confident will not live long enough to wear out before they fatigue? Why would you make a product where a majority of the users abuse your product? Even if you do not warranty the product for more than a year it certainly doesn't make people feel confident in your brand, does it?
If I were King I would do away with ST type tires and require a 20% load margin on LT type tires in RV trailer application and require TPMS on all RVs.


But I'm not King so all I can do is offer suggestions to help people get better tire life.

Good post Tireman. #4 is perplexing to me. Because the TV can pull the trailer at 65, 75, 100 mph is irrelevant. Why would we expect them to slow down? To me it's obvious; what in the world would 90% of the folks towing a 10-15k trailer at 80mph do in an emergency; right here, right now, he just pulled in front of me moment? First they would mess their pants, secondly they would try some "evasive" maneuver at 80 mph with a huge load behind them that they can't control and then.....wind up splattered along the roadside...or, mess their pants, say "honey hold on" and let the trailer drive them into some unsuspecting individual causing catastrophic damage to the driver, his/her family and the other individuals.

Anyone, IMO, that is willing to drive the speed that the tires are rated for (above 65-70mph) with a trailer behind them because they can....needs to have the trailer and their license removed - you absolutely can't control it like an unloaded car/truck.

I don't get to be King either but it is fun/enlightening to share our opinions/observations/thoughts. JMO
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Old 06-11-2019, 07:39 PM   #37
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Quote:
Originally Posted by Tireman9 View Post
OK Here is kind of my overview of tires.
1. The basic format for load capacity is Size (air volume) x PSI x K
2. The "K" is supposed to be a factor that relates to the tire service. If a tire is normally run with a 25% Reserve Load (to account for occasional low inflation or high load) on the improved highway for 3 to 5 years, you might have a high K factor like 1.1. On the other hand, if a significant portion of the population of tires will be operated under-inflated or overloaded and you want 10 years life then the k should be a lower value like maybe .80. But what happens when the vehicle design imparts excess belt stress sometimes 24% higher than seen on normal motor vehicles? The K factor should be reduced significantly. Maybe even 24% to 0.65

2. The RV industry lobbied long and hard to not upgrade the durability improvements that were placed on P and LT tires in 2002. Why? They didn't want to spend more on tires. DO they care more about their bottom line than you having no tire problems? What do you think? They didn't have a tire problem. They followed the standards instructions. The tire industry had the problem by allowing tires without any load capacity reserves to be used as OEM on RV trailers.

3. The ST load formula was based on a MAX speed of 65 with normal highway speed of 55. (IMO the tire manufacturer's are using a different formula. What else would explain the ST tire industry wide speed ratings going to as high as 87 MPH? Is NHTSA looking the other way?
4. Given that the RV trailer travels at the same speed as the tow vehicle, why would you expect people to slow down when the strong engine can easily pull at 80 mph?
5. What is the difference between an LT tire and an ST tire today? They both travel at the same speed on the same roads. The LT only needs to last 4 to 5 years but the RV tire does not wear out till 10 years + in many cases.
6. Under what logic would you expect a tire with the letters "ST" on the sidewall to be able to carry 20% more load than a tire with the letters LT on the sidewall. The physics of Size x PSI still holds but now the operational speed of the LT and ST are the same. (Carlisle CEO told Modern Tire in an interview that ST tires use larger & stronger cording. Do you have information that makes that untrue?)
7 If there were some magic rubber that allowed a company to make tires that can carry 20% more load (the difference between LT and ST) Why wouldn't the company put that "Super" compound in their premium LT tire line? (Just maybe the different stresses in the LT design wont permit it...The load capacity of the GY G614 RST LT235/85R16 LRG comes to mind.

8 Only a few tire companies make ST tires. Ever wonder why? (Labor Costs.)Do you think it's possible that they do not want to make tires that they can be fairly confident will not live long enough to wear out before they fatigue? Why would you make a product where a majority of the users abuse your product? Even if you do not warranty the product for more than a year it certainly doesn't make people feel confident in your brand, does it? Read the new Triangle USA ST tire warranty.)
If I were King I would do away with ST type tires and require a 20% load margin on LT type tires in RV trailer application and require TPMS on all RVs.


But I'm not King so all I can do is offer suggestions to help people get better tire life.
Most of the ST tire manufacturers are right up front with providing ST tire life expectancy.

There are numerous posts where the writer makes comments about ST tire mileage. They are not mileage tires. I've never seen ST tire warranty for mileage.

I've always said a tire's warranty is a good indicator of its manufacturers confidence in the tire's durability. Many of todays tire warranty packages - all designs - are very comprehensive and worth reading.
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Old 06-13-2019, 10:32 AM   #38
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To CWtheMan
Answering your comments/questions:
"They didn't have a tire problem. They followed the standards instructions. The tire industry had the problem by allowing tires without any load capacity reserves to be used as OEM on RV trailers."
Well CW, as you know it is the responsibility of the vehicle MFG to select the tires and to specify the necessary inflation needed to support the GAWR. The Regulations do not say "Carry the GAWR plus bit more"

===========
"(IMO the tire manufacturer's are using a different formula. What else would explain the ST tire industry-wide speed ratings going to as high as 87 MPH? Is NHTSA looking the other way?"
The formula has not changed. The proof of that can be confirmed simply by looking at the Load/Infl tables from the '70s and comparing with the current tables.
The Speed ratings were added, almost overnight, to address Federal Trade Commission, not DOT rules on tariffs on non-speed tires vs speed rated tires. Given the stated 1 year warranty some might think that since it is possible for a tire to run to a higher than 65 mph speed for a few hundred or even a couple of thousand miles some might have decided to play the odds. NHTSA simply requires tires to be capable of passing certain well-defined tests and uses the Tire Industry published Load & Inflation tables when setting the test conditions.

==========
"(Carlisle CEO told Modern Tire in an interview that ST tires use larger & stronger cording. Do you have information that makes that untrue?)" Since it is the air pressure that supports the load, not the tire structure the "strength" of the body cord is not an issue.
Body construction strength can be achieved using a number of different materials and for each material, cords are made in dozens of different configurations. Even the number of "cords per inch" can be adjusted such that fewer cords of larger or stronger material can be substituted for more cords that are smaller or not as strong. So it's entirely possible to have larger and stronger cords yet end up with a weaker sidewall. So the statement can be true but is not a requirement for ST type tires. Think for a moment of using smaller and fewer steel cords vs larger and more polyester. So which is "Better"?
==============

Having designed Indy type, Truck, LT, P-type and even Temporary spares I see no limit in the designs to what materials could be used. In my career, I have used and evaluated Nylon, Polyester, Steel, Rayon and Fiberglass in numerous levels of size and strength. While each may have a balance of cost vs performance that pushes the design engineer to select one combination over another. BUT as I said if just using "larger & stronger cording" somehow allowed a tire to carry 20% more load why wouldn't a company increase the load capacity of their LT tires to beat the competition?

I read the Triangle USA warranty. Sounds fine to me, so why don't we see lots of RV trailers sold with Triangle brand? I have no idea.

You may not know that Goodyear was the company that introduced the ST type tire, over the objections of other tire companies in US Tire & Rim Association according to a contact I have in the tire industry.

RE why other major tire companies don't make ST type? We can only guess but I don't see the cost of making the tires as the reason.
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Old 06-13-2019, 01:58 PM   #39
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Can you guys do this in a PM?
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Old 06-13-2019, 04:59 PM   #40
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As I said in post #29, BLAH, BLAH, BLAH!!!!!!!
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