Something to read about trailer tires part one

Loco

Well-known member
Here is something everyone worried about tire should read. It will be in two part because of size.

The subject of tires is hard to escape these days. It seems every TV newscast or daily paper has a story on faulty automobile tires. As a result of negative publicity and a plethora of litigation, the tire industry is in the middle of self-analysis. Manufacturers, industry organizations and regulators are now coming forward with new recommendations concerning tire selection, maintenance and replacement.
Since knowledge and proper equipment are the keys to a pleasant, trouble-free towing experience, we decided to take a fresh and in-depth look at tires for trailers. The new information and thinking we uncovered from manufacturers surprised us.
For example, though your trailer's tires may sport plenty of tread and have healthy-looking sidewalls (that are free of cracks), the same tires may be disintegrating from within, manufacturers tell us. Like time bombs, tires can let go without warning.
A blowout on a single-axle trailer can spell disaster. A sudden shift in weight can create an unstable load and trigger a rollover. Yet, even on a tandem- or triple-axle trailer, the results can be unpleasant, and may spark a chain reaction as the remaining tires bear an overwhelming load and fail as a result.
Before we explore why seemingly sound trailer tires can fail, let's talk about selecting the right tires for your trailer in the first place. When it comes to trailer tires, what you don't know can hurt you.
THE RIGHT TIRES
When purchasing or replacing trailer tires, look for the ST (Special Trailer) designation. Avoid using a passenger car (P) tire or light truck (LT) tires, as these do not have stiff, beefy sidewalls and other structural components to provide stability and handle the stress and dynamics imposed by a trailered load. Modern ST tires feature materials and construction to meet the higher load requirements and unique demands of trailering.
"The major difference is reflected in the polyester cords used in ST tires," said Tim Fry, senior development engineer with Goodyear Tire & Rubber Co. in Akron, Ohio. "These cords are bigger than they would be for a comparable P or LT tire. Typically, the steel wire also has a larger diameter or a greater tensile strength to meet the additional load requirements.
"Because of the heavier construction for an equal volume of air space, an ST tire is designed to carry more load (than a P or LT)," says Fry.
What's more, the ratings on ST tires are standardized for axle ratings on trailers, according to Leo Garbarino, regional sales director for Carlisle Tire and Wheel Co. of Aiken, South Carolina. "If you have a 5000-pound axle, use an ST tire rated at 2540 pounds, so that two tires will meet the 5000 pound requirement in weight-carrying capacity," said Garbarino. "A P or LT tire is not rated the same way, so determining the load capacity can be difficult."
separationAnxietyCallout1.gif
If the combined tire ratings do not meet the axle ratings, the tires will eventually fail-perhaps in a catastrophic blowout.
Bias ply trailer tires normally have two belts of steel in the tread area and extra sidewall cords to add stiffness. Most tires also include nylon belts to help resist separation caused by overloading, underinflation or excessive speed.
FAILURE ANALYSIS
Even properly rated tires can fail. The No. 1 cause is underinflation. This is particularly true of an ST tire, which relies on proper inflation to live up to its load rating. Without enough air pressure, an ST sidewall will not function as designed, and will eventually fail, usually in the form of a sidewall blowout. Tires lose approximately 1 psi per month as well as 1 psi for every 10-degree drop in temperature. Overinflation is also hard on a tire, causing irregular wear and possibly a blowout. Yet, you can't always spot improper inflation with a visual inspection, so check your tires frequently with an accurate air-pressure gauge.
Long-term fatigue can also weaken a trailer tire. There are a number of factors that accelerate fatigue, but heat buildup from towing at high speeds is one of the main culprits, according to Fry.
"If you trailer nonstop from Phoenix, Arizona, to Las Vegas, in 100-degree temperatures at 65 mph, you use up much of the resources of that tire, and you don't realize it," said Fry.
Fry is not talking about wearing out the tread. It is the tire's construction that is breaking down. As heat builds up, the tire's structure starts to disintegrate and weaken. Over the course of several trips, this load-carrying capacity gradually decreases, according to Fry. Incidentally, all ST tires have a maximum speed rating of 65 mph.
One key to extending tire life on a tandem- or tri-axle trailer is to ensure that the trailer is riding level, thus distributing the load equally among all the tires. If the trailer tongue sits too high, the rear tires may bear the brunt of the load: with the trailer tongue too low, the front tires may be unduly stressed.
OLD MAN TIME
Time and the elements can also weaken a tire. The structural components and bonding agents slowly break down. This is due primarily to internal air pressure forcing oxidation of the tire materials. Ultraviolet rays also attack the rubber on a tire left exposed to the sun. As a result, a 15-year-old tire that was rarely used may look virtually new, but because of the ravages of time and elements, it does not have the same strength as when it was new, according to Fry. "As an estimate, in about three years roughly one-third of a tire's strength is gone, just because of the normal process of aging," Fry claimed. "We believe three to five years is the projected life of normal trailer tires."
kotspacer.gif
REPAIRING ST TIRES
Should you repair a flat trailer tire? The answer depends on the size of the puncture, its location and method of repair. If it is a small hole in the tread area, it can be successfully patched. However, if it is a jagged cut or a puncture in the sidewall, replace the tire.
There is only one way to properly repair a flat tire, and it is important to have it fixed as quickly as possible. You must remove the tire and patch it from the inside. You must also plug the hole from the outside. If moisture gets into the tire and reaches the steel belt, the steel will begin to rust in seven to 14 days. Three months later, the rust will cause a weak spot in the tire. That will lead to a separation.
Whenever you repair or replace a tire, always put on a new valve stem. Heat and age deteriorate the rubber in the stem and this results in leakage.
 

mesteve

Well-known member
Plugging your own company huh?

Edit: disregard, offending post removed.
 
Last edited:

RollingHome

Well-known member
mesteve, thanks for pointing that out. I apoligize, I missed the name of Loco's company (too many words)... would you be so kind as to tell me the name of Loco's company, so I can avoid it ? In advance, thank you. Tom
 

mesteve

Well-known member
mesteve, thanks for pointing that out. I apoligize, I missed the name of Loco's company (too many words)... would you be so kind as to tell me the name of Loco's company, so I can avoid it ? In advance, thank you. Tom

Disregard as the offending post has been removed. There was a post in between mine and Loco's.
 
Something I wanted to add to this great post is that my experience has shown that most people overload their trailers and thus their trailer tires. All tires have a maximum load carrying capacity and thus need to be followed. Trailer tires have a load rating stamped on the sidewall of the tire. This load rating, corresponds to a ply rating in addition to a specific load carrying capacity specific to the size of trailer tire. As an example, LRC implies that the tire is 6 ply rated, while LRD implies it is 8 ply rated. You should check with the manufacture to see what that rating corresponds to for maximum load carrying capacity and then FOLLOW that recommendation!

Here is something everyone worried about tire should read. It will be in two part because of size.

The subject of tires is hard to escape these days. It seems every TV newscast or daily paper has a story on faulty automobile tires. As a result of negative publicity and a plethora of litigation, the tire industry is in the middle of self-analysis. Manufacturers, industry organizations and regulators are now coming forward with new recommendations concerning tire selection, maintenance and replacement.
Since knowledge and proper equipment are the keys to a pleasant, trouble-free towing experience, we decided to take a fresh and in-depth look at tires for trailers. The new information and thinking we uncovered from manufacturers surprised us.
For example, though your trailer's tires may sport plenty of tread and have healthy-looking sidewalls (that are free of cracks), the same tires may be disintegrating from within, manufacturers tell us. Like time bombs, tires can let go without warning.
A blowout on a single-axle trailer can spell disaster. A sudden shift in weight can create an unstable load and trigger a rollover. Yet, even on a tandem- or triple-axle trailer, the results can be unpleasant, and may spark a chain reaction as the remaining tires bear an overwhelming load and fail as a result.
Before we explore why seemingly sound trailer tires can fail, let's talk about selecting the right tires for your trailer in the first place. When it comes to trailer tires, what you don't know can hurt you.
THE RIGHT TIRES
When purchasing or replacing trailer tires, look for the ST (Special Trailer) designation. Avoid using a passenger car (P) tire or light truck (LT) tires, as these do not have stiff, beefy sidewalls and other structural components to provide stability and handle the stress and dynamics imposed by a trailered load. Modern ST tires feature materials and construction to meet the higher load requirements and unique demands of trailering.
"The major difference is reflected in the polyester cords used in ST tires," said Tim Fry, senior development engineer with Goodyear Tire & Rubber Co. in Akron, Ohio. "These cords are bigger than they would be for a comparable P or LT tire. Typically, the steel wire also has a larger diameter or a greater tensile strength to meet the additional load requirements.
"Because of the heavier construction for an equal volume of air space, an ST tire is designed to carry more load (than a P or LT)," says Fry.
What's more, the ratings on ST tires are standardized for axle ratings on trailers, according to Leo Garbarino, regional sales director for Carlisle Tire and Wheel Co. of Aiken, South Carolina. "If you have a 5000-pound axle, use an ST tire rated at 2540 pounds, so that two tires will meet the 5000 pound requirement in weight-carrying capacity," said Garbarino. "A P or LT tire is not rated the same way, so determining the load capacity can be difficult."
separationAnxietyCallout1.gif
If the combined tire ratings do not meet the axle ratings, the tires will eventually fail-perhaps in a catastrophic blowout.
Bias ply trailer tires normally have two belts of steel in the tread area and extra sidewall cords to add stiffness. Most tires also include nylon belts to help resist separation caused by overloading, underinflation or excessive speed.
FAILURE ANALYSIS
Even properly rated tires can fail. The No. 1 cause is underinflation. This is particularly true of an ST tire, which relies on proper inflation to live up to its load rating. Without enough air pressure, an ST sidewall will not function as designed, and will eventually fail, usually in the form of a sidewall blowout. Tires lose approximately 1 psi per month as well as 1 psi for every 10-degree drop in temperature. Overinflation is also hard on a tire, causing irregular wear and possibly a blowout. Yet, you can't always spot improper inflation with a visual inspection, so check your tires frequently with an accurate air-pressure gauge.
Long-term fatigue can also weaken a trailer tire. There are a number of factors that accelerate fatigue, but heat buildup from towing at high speeds is one of the main culprits, according to Fry.
"If you trailer nonstop from Phoenix, Arizona, to Las Vegas, in 100-degree temperatures at 65 mph, you use up much of the resources of that tire, and you don't realize it," said Fry.
Fry is not talking about wearing out the tread. It is the tire's construction that is breaking down. As heat builds up, the tire's structure starts to disintegrate and weaken. Over the course of several trips, this load-carrying capacity gradually decreases, according to Fry. Incidentally, all ST tires have a maximum speed rating of 65 mph.
One key to extending tire life on a tandem- or tri-axle trailer is to ensure that the trailer is riding level, thus distributing the load equally among all the tires. If the trailer tongue sits too high, the rear tires may bear the brunt of the load: with the trailer tongue too low, the front tires may be unduly stressed.
OLD MAN TIME
Time and the elements can also weaken a tire. The structural components and bonding agents slowly break down. This is due primarily to internal air pressure forcing oxidation of the tire materials. Ultraviolet rays also attack the rubber on a tire left exposed to the sun. As a result, a 15-year-old tire that was rarely used may look virtually new, but because of the ravages of time and elements, it does not have the same strength as when it was new, according to Fry. "As an estimate, in about three years roughly one-third of a tire's strength is gone, just because of the normal process of aging," Fry claimed. "We believe three to five years is the projected life of normal trailer tires."
kotspacer.gif
REPAIRING ST TIRES
Should you repair a flat trailer tire? The answer depends on the size of the puncture, its location and method of repair. If it is a small hole in the tread area, it can be successfully patched. However, if it is a jagged cut or a puncture in the sidewall, replace the tire.
There is only one way to properly repair a flat tire, and it is important to have it fixed as quickly as possible. You must remove the tire and patch it from the inside. You must also plug the hole from the outside. If moisture gets into the tire and reaches the steel belt, the steel will begin to rust in seven to 14 days. Three months later, the rust will cause a weak spot in the tire. That will lead to a separation.
Whenever you repair or replace a tire, always put on a new valve stem. Heat and age deteriorate the rubber in the stem and this results in leakage.
 

GOTTOYS

Well-known member
What a crock! Looks to me like Tire Hobby er Fast Eagle has come up with another new handle and is trying to pawn his ST tire agenda off on everybody again...Don
 
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