General Question about Tires

[SummitPond]

In perusing the discussions about tires, I note a lot of concern regarding UV.

Are trailer tires made differently than car tires? I don't recall ever hearing about UV issues with car tires (in the general media ... I'm new to the forum area). We don't "protect" car tires with covers like discussed for trailers. Should we? Or am I missing something?

Thanks.

Ken

[bsmith0404]

They all have the same type of UV inhibitors in them. Part of the problem with RV tires is that they tend to sit in one place unlike auto tires. Not 100% accurate, but an easy way to explain it is that the UV inhibitors work their way through the rubber as the tire spins. When the tires are not used they can break down and the sun/UV rays typically beat on the same portion of the tire day after day. How much difference it makes to cover the tires is debatable, I think for the most part it is peace of mind knowing that we are at least doing something to help slow the deterioration.

[randy69]

When st tires are made in China. What agency determine what standards of uv protection and grade of rubber used? There really isn't one. Lt tires are the way to go. Usa made. And if many problems would accrue,like Firestone in the day.you would definitely here it on TV or news paper. And correction would be made.

[bsmith0404]

When st tires are made in China. What agency determine what standards of uv protection and grade of rubber used? There really isn't one. Lt tires are the way to go. Usa made. And if many problems would accrue,like Firestone in the day.you would definitely here it on TV or news paper. And correction would be made.

All tires sold in the US regardless of where they are manufactured must meet DOT standards and have the DOT certification on the sidewall. Part of the DOT certification is tire construction and safety requirements.

[randy69]

Ok so why do we see so many st tire problems. And not so many LT. tire problems on our RV rigs??. And not referring to one sitting in the driveway for months. But some one that really uses there rig a lot. .? sure makes me wonder .?

[bsmith0404]

Personal opinion, people don't take care of their ST tires. I'm not accusing those who have had problems, but I see a lot of trailers going past me on the roads at 75-80, tires are carrying a lot of weight and building a lot of heat. They don't properly inflate them and they basically abuse them. I have been towing trailers, boat, car, and Rv for over 25 years and probably have close to 100k miles on ST tires and have never had a failure. My dad has been towing longer than me and has never had a failure. I am very particular about my tires, take breaks while towing and reduce speed to keep heat down. I keep my tires balanced and check alignment on the trailer. I can't speak for every problem each different person has had, but I am surprised by the numbers. If it was all because of Chinese made ST tires, I should have had at least one by now......hopefully I didn't just jinx myself :) The debate between LT vs ST has gone back and forth, each has their own experience and opinions. I prefer ST, and yes I prefer US made. I cannot tell you the difference between US and foreign made tires, but I can say they all meet DOT requirements. I really wish it was easy to point to every tire failure and say xyz is why it happened. I can say that although I've never had an ST tire fail, I have had LT tires on the TV fail while towing, it was made in the US.

[CWtheMan]

Tire compounding is allowed to be confidential. Only a legal matter will allow that confidentially to be broken.

DOT certification is a requirement all highway tires must go through. DOT (NHTSA) writes the particulars. The actual testing is normally done by third party contractors experienced in the particulars.

Finger pointing is easy. Actually establishing that any tire is unsafe or improperly tested or doesn’t meet the standards is much more difficult to prove. Even tire recalls are normally self imposed by the individual tire builder.

A tire is what it says it is on its sidewall until someone can prove it’s not.

CW

[CWtheMan]

Basically ST tires are what they say they are. The information is in print. ST tire owners (users) just don’t take the time to discover the differences from P or LT tires they are more familiar with.

Carlisle Tire - a long time manufacturer of ST tires - has often told us that ST tires will degrade up to 10% per year. The closer they are used to their maximum load capacity the faster they get to the end of their life cycle (3-5 years).

Lots of people are concerned with tire mileage. ST tires are not mileage tires. They are age out tires. The more stress an owner puts on them the faster they get to their individual age limit.



CW

[BulletOwner1]

They all have the same type of UV inhibitors in them. Part of the problem with RV tires is that they tend to sit in one place unlike auto tires. Not 100% accurate, but an easy way to explain it is that the UV inhibitors work their way through the rubber as the tire spins. When the tires are not used they can break down and the sun/UV rays typically beat on the same portion of the tire day after day. How much difference it makes to cover the tires is debatable, I think for the most part it is peace of mind knowing that we are at least doing something to help slow the deterioration.

I generally concur. I will add that sitting idle and age have a lot to do with it. When we had our motor home I looked into tire issues more. RV tires can stay on the unit for years and still have a lot of tread left, LOOKING fine. My motor home tire maker said that regardless of tread depth that the tire needed replacement after 6 or 7 years (can't recall precisely). That was because other factors, other than tread depth, dictated the safe life of the tire. And pretty much most RV's out there don't have a great deal of miles on them but because of age, should be replaced.

[randy69]

It seems too me, the correct tire would be individuals that do not travel long distances, or rv less than 6 times a year, ST tires would be the way to go. But full timers, LT tires might be that way to go. There is a huge price difference ST VRS LT. Personally Lt tires Still wins in my book. Mitchlin xp ribs. 80 psi

[bsmith0404]

It seems too me, the correct tire would be individuals that do not travel long distances, or rv less than 6 times a year, ST tires would be the way to go. But full timers, LT tires might be that way to go. There is a huge price difference ST VRS LT. Personally Lt tires Still wins in my book. Mitchlin xp ribs. 80 psi

A lot of people have had good luck with these tires. My only problem is the load index of 120 is only rated for 3042 lbs at 80 psi, typical for an LT tire. My Carlisle F range (load index of 128) are rated for 3960. I'd lose nearly 4,000 lbs of payload capacity. I have over 11,000 lbs on the axles (11,600 that last time I scaled it), that isn't much breathing room. Too close for comfort for me regardless of what type/brand of tire it is. The one advantage to the ribs is that they are a commercial truck tire, so they are a heavy duty and a very good tire.

[sourdough]

A question was posed asking why we don't hear about all the tire failures from passenger and truck tires vs st tires. Sitting, age, sun exposure etc. all take their toll on any tire; car, truck or trailer. Most trailers are not on the road every day rolling up 20-40k miles per year like many car tires. The car tires actually wear out vs aging out. My mother in law drives 3k miles or less per year. I replace her car tires every 4-5 years, not due to tread wear, but due to aging. At 3 years I begin airing down her tires when she visits until the sidewall gets a nice bulge and check for spider cracks from age. When they appear, I put a new set of tires on the vehicle. I replaced them 2 weeks ago. The tire shop owner looked at the tires and asked me what was wrong....they looked new. I had him pull them off then bent the sidewall and showed him the little spider cracks. Since she is 89 and still likes to drive to the grocery store in her town he agreed it was better not to have something like that that could go wrong. Same goes for trailer tires IMO.

[CWtheMan]

When st tires are made in China. What agency determine what standards of uv protection and grade of rubber used? There really isn't one. Lt tires are the way to go. Usa made. And if many problems would accrue,like Firestone in the day.you would definitely here it on TV or news paper. And correction would be made.

Uniform Tire Quality Codes (UTQC) are not required for ST and LT tires. UV chemical protection is part of the tire’s chemical compounds which are considered confidential. Tire manufacturers just don’t give out that information other than saying the protection is there.

CW