There have been soooo many threads and posts on ST tires here about what the best one is and why they fail sometimes. I was just reading one of those "threads from heck" - ST tire thread from heck...But I don't see much if any discussion in that thread or elsewhere on the following:For those that live on the west coast (like us), when you buy a travel or 5th wheel trailer (unless it's a really small one), it gets towed to the dealer by a delivery driver. That means if it comes from a plant in Indiana, where most of them seem to, you have over 2,000 miles on the tires. I've read some say that ST tires should be replaced at 5,000 mile intervals so this means that your brand new travel trailer has tires that are about 1/2 used before you take it for the 1st camping trip. I think it's just plain wrong for this to happen. I think this could easily be one factor in premature wear or failure for west coast owners.And to go further on the delivery driver thing, if a driver is paid by the mile, it seems to me they will be motivated to get to their destination sooner than later. This means they could easily be driving in excess of 65mph for extended periods. And they may also be hitting lots of potholes, bumps and cracks. None of this is good for ST tires. And if the driver is driving a long distance like to the west coast, your ST tires could have taken a lot of abuse during shipment. How would you ever know? You could have over 2,000 miles of hard abuse and you'd never know looking at the new TT on a dealer's lot. I would hazard a guess that this is one contributing factor in tire blowouts. Of course the first reaction in a blowout would be it was "those cheap Ch*nese tires".It's my understanding that hitting a lot of bumps, cracks and potholes in the roads is bad, especially at higher speeds. The I-5 in northern Cal. has settlement between adjacent concrete slab sections. We have had 5 tires damaged there. Two on a car and 3 on a new Toyota truck. In each case, the steel cords snapped and caused lumps in the treads. The Toyota dealer replaced the OEM Michelin tires under warranty. I have to think that hitting big enough bumps, cracks and potholes often and heard enough can lead to damaged cords and bulges in ST tire treads.I've read elsewhere that "curbing" ST tires is not good because of how the sidewalls are made. Just how bad is curbing ST tires? Is once bad or would you have to do it many times to cause damage?Some TT frames/suspensions have a lot of flex in them. This can cause tires/wheels to go quite a bit out of camber when the trailer weight gets "thrown" side to side as in cornering and lane changing at speed. For example, the trailer in this photo is being pulled out of a tight spot in a campground and you can see how much the frame and suspension flexes causing the tires to be way off camber. You have to know that the tires will move out of camber as the trailer is moving down the freeway or being pushed to one side around a corner. I'm guessing that this happens more than TT owners may realize.I just think that there are other reasons ST tires fail other than not being at the correct PSI or they are driven frequently over 65mph. To be sure, there are better ST tires out there like Maxxiss, Carlisle or even Marathon, and there are many at the lower end of quality. But to say just because the tires are made in China is not THE reason people report so many ST tire failures. This website is a good read and the author has spent a lot of time in the tire industry. RV Tire SafetyOn a bit of a related note, I asked a local dealer why you would want to go with the GY Marathon tire upgrade option they have on a certain brand over the Freestar load range C tires that come with the TT, and they had no answer. Apparently they don't get many asking to spend extra $$ on upgraded tires. I wonder how often this happens out there and owners really do end up with inferior quality tires and they could have upgraded to better tires at the start for little extra cost and perhaps have avoided a blowout?Not looking to start a heated debate, especially since today is Remembrance Day... (no WWW III please) Just wondering and just looking for some easy-going thoughts.

All true but....The main reason for all of those is the low build/testing requirements for ST tires. LTs are built and tested to much more demanding standards. That is why LTs solve the problem.You can go on forever making excuses for why STs fail. Or you can get LTs and solve the problem.

excuse me, but where did you read that ST need to be replaced every 5000 miles? I've put 5000 on this year and they are no where near replacement.

Forgive the stupid question, but what are ST tires? Also, my tires have 3,000 miles on them since I bought it (I am on the west coast) and there is no detectable tread wear. What is the issue?

n7bsn wrote:excuse me, but where did you read that ST need to be replaced every 5000 miles? I've put 5000 on this year and they are no where near replacement.From Discount Tire's website (5,000 to 12,000 miles):Discount TireFrom the Carlisle website (5,000 to 12,000 miles or more):Carlisle Tire

Not to mention does the factory driver check pressure before leaving? Doubtful.

Other reasons ST tires fail?? | Good Sam Community

35 Replies

Huntindog
Explorer
Nov 13, 2013
CapriRacer wrote:
LarryJM wrote:
Too bad you can't remember the actual numbers, but I still think the opposite of what you think might be true. One real issue with using things like race car or similar scales is that they are fine for things like cars where the weights on the tires are distributed at for separate corners, but on tandem axle trailers putting a scale under one tire on a side will give you erronous numbers...........

Larry

I'm not going to quote the entire posting - takes up too much space.

Larry, it's obvious you've never seen race car scales. There are 4 pads and part of the set up is to make sure they are level. I am sure that anyone who would use them would be aware of this.

Second, EVERY time I have seen published results from a weighing of trailer where they did individual tires, there has been variation. I have seen enough of these to feel comfortable making this statement:

Because I want to give conservative advice (that is, one that is certain to produce good results) I recommend that if the trailer is weighed axle by axle, that people use a 10% factor to get the max load - and 15% if the weigh all 4 tires at once.

I'd like to see more individual weighings to further refining the number, but it doesn't appear to be very far off. - keeping in mind that I am looking for the maximum variation.
Thanks, Capri. You beat me to it. That is exactly what I used. I was on a sprint car pit crew at that time. Got to play with some VERY expensive toys back then.

And as for the water tanks... My first TT had the fresh water tank on the side, under some cabinents. Emptying it into the other tanks would for sure change some weights. There are lots of things that can change during a trip. That three cases of beer ;)under the dinette won't be there on the trip home, food in the fridge plus the cold case of beer:B in there will be gone as well.
I think it is MORE likely that weights will vary at some point than not.:B
thewhitehat
Explorer
Nov 13, 2013
From Discount Tire's website (5,000 to 12,000 miles):
Discount Tire

From the Carlisle website (5,000 to 12,000 miles or more):
Carlisle Tire

But wait a minute! You didn't read the section of the Discount Tire site where it explains: "Why use an ST Tire".
CapriRacer
Explorer II
Nov 13, 2013
LarryJM wrote:
Too bad you can't remember the actual numbers, but I still think the opposite of what you think might be true. One real issue with using things like race car or similar scales is that they are fine for things like cars where the weights on the tires are distributed at for separate corners, but on tandem axle trailers putting a scale under one tire on a side will give you erronous numbers...........

Larry

I'm not going to quote the entire posting - takes up too much space.

Larry, it's obvious you've never seen race car scales. There are 4 pads and part of the set up is to make sure they are level. I am sure that anyone who would use them would be aware of this.

Second, EVERY time I have seen published results from a weighing of trailer where they did individual tires, there has been variation. I have seen enough of these to feel comfortable making this statement:

Because I want to give conservative advice (that is, one that is certain to produce good results) I recommend that if the trailer is weighed axle by axle, that people use a 10% factor to get the max load - and 15% if the weigh all 4 tires at once.

I'd like to see more individual weighings to further refining the number, but it doesn't appear to be very far off. - keeping in mind that I am looking for the maximum variation.
LarryJM
Explorer II
Nov 13, 2013
Huntindog wrote:
LarryJM wrote:
Lantley wrote:
In the end my experience has been ST tires are inferior. Had all kinds of issues. They ALL magically went away when I upgraded to LT tires. There are many people that tell the same tale. Problems,blowouts,flats with ST's changed to LT tires and all problems solved.
One of the issues that still exist are the tires are marginally rated. The idea that all 4 tires carry equal weight is part of the fallacy. One tire is often overloaded and over stressed from the start. Floorplans are not balance by weight. Why do we expect the tires to carry equal weight?
ST tires are built to marginal/inferior standards vs. and LT. ST tires are not built to a standard that entails transporting humans. They are built and regulated to a cargo only standard. In the end they are inferior. LT's are built for passenger carrying vehicles and are simply a more reliable tire built with better quality control as a result.
LT tire upgrades continue to resolve the blowout issue.

I'm not so sure one can just assume like you have done that there is significant unequal loading on tires on a tandem axle trailer especially side to side. Unless the trailer is being towed in a non level configuration front to back there should be minimal differences in the front and back tires on the same side. As to side to side I have actually weighed my trailer fully loaded side to side and there was only a 50lb difference in the weights and that is for a totaltwo axle weight of close to 7,000lbs. I would think a better assumption for the majority of trailers is they are designed to have a fairly even side to side wt. distribution unless you have significantly modified the insides. I'm sure there are exceptions to this, but I think one can safely assume that there is a fairly good side to side balance in the axle weights for a factory configured TT/5er.

Larry
I had access to race care suspension setup scales when I had my previous TT. A seperate scale for each wheel.
I don't recall the numbers, but do remember being surprised at how much they differed.
Even if the TT left the factory with perfectly distributed weights on all tires....That all goes out the window when the consumer starts loading it.
Even in use, water leaves the fresh tank and ends up in the black or grey tank. depending on just where the tanks are located, this alone can throw the weight distribution off.

Too bad you can't remember the actual numbers, but I still think the opposite of what you think might be true. One real issue with using things like race car or similar scales is that they are fine for things like cars where the weights on the tires are distributed at for separate corners, but on tandem axle trailers putting a scale under one tire on a side will give you erronous numbers since the two tires on that side are not on the same level, but are basically uneven ... like having the trailer not level front to back. For a normally loaded and level trailer, I would bet there is most likely 10% or less variance from the weight on the lightest wheel to the weight on the heaviest wheel and those two biggest deltas won't be on the same side of the trailer. Again, the trailer must be fairly level front to back (torsion axle trailers are most sensitive to this) and the wheels on each side have to be on a flat surface. My WAG would be most trailers will see less than a 200lb delta between all 4 wheels for a pair of 3500lb axles and somewhere around a 100lb MAX delta between the wheels on the same sides of the trailer. To me that is not significant or bad.

As far as tanks again I'm sure there are exceptions, but most I think you will find are basically centered between the frame rails so they won't cause side to side weight variances, only front to back and again as long as the trailer is level the uneven contribution between axles should not be that significant.

Of course I'm assuming a normally loaded trailer and not one completely empty since there by design there will be the max side to side wt. differences since things like the Frig, water heater, and the kitchen area will be empty.

Larry
Huntindog
Explorer
Nov 13, 2013
LarryJM wrote:
Lantley wrote:
In the end my experience has been ST tires are inferior. Had all kinds of issues. They ALL magically went away when I upgraded to LT tires. There are many people that tell the same tale. Problems,blowouts,flats with ST's changed to LT tires and all problems solved.
One of the issues that still exist are the tires are marginally rated. The idea that all 4 tires carry equal weight is part of the fallacy. One tire is often overloaded and over stressed from the start. Floorplans are not balance by weight. Why do we expect the tires to carry equal weight?
ST tires are built to marginal/inferior standards vs. and LT. ST tires are not built to a standard that entails transporting humans. They are built and regulated to a cargo only standard. In the end they are inferior. LT's are built for passenger carrying vehicles and are simply a more reliable tire built with better quality control as a result.
LT tire upgrades continue to resolve the blowout issue.

I'm not so sure one can just assume like you have done that there is significant unequal loading on tires on a tandem axle trailer especially side to side. Unless the trailer is being towed in a non level configuration front to back there should be minimal differences in the front and back tires on the same side. As to side to side I have actually weighed my trailer fully loaded side to side and there was only a 50lb difference in the weights and that is for a totaltwo axle weight of close to 7,000lbs. I would think a better assumption for the majority of trailers is they are designed to have a fairly even side to side wt. distribution unless you have significantly modified the insides. I'm sure there are exceptions to this, but I think one can safely assume that there is a fairly good side to side balance in the axle weights for a factory configured TT/5er.

Larry
I had access to race care suspension setup scales when I had my previous TT. A seperate scale for each wheel.
I don't recall the numbers, but do remember being surprised at how much they differed.
Even if the TT left the factory with perfectly distributed weights on all tires....That all goes out the window when the consumer starts loading it.
Even in use, water leaves the fresh tank and ends up in the black or grey tank. depending on just where the tanks are located, this alone can throw the weight distribution off.
LarryJM
Explorer II
Nov 13, 2013
gmw photos wrote:
Just to try to clarify, the Kumho is marketed around the world as a van/truck tire. It is marketed in the USA as a trailer tire. A likely guess is that Kumho sees little need to market a LT tire in the US that is a 14" tire, because trucks and SUV's here typically use 16" tires. I would guess the american marketing of this LT tire as suitable for trailers is a smart move on their part as they understand they are offering a high quality tire for the towable market at prices that compare to ST pricing from other providers.

The following quote from the Kumho site in the United Kingdom:
========================

"Radial 857

Modern tyres for people carriers

Excellent driving characteristics in dry and wet conditions
High steering precision
Superb traction
Durable for high mileage
Extremely smooth-running and comfortable
Robust carcass structure
For vans, people carriers and mobile homes"
===========================

....and a pic of the sidewall of one of the 857's on my trailer:

Can't argue with what you said, but one should remember that the Kumho 857 is sort of a unique beast in that it is really not a tire designed or meant for the American market and my prior post on it not being a LT tire was mainly meant to caution one that as we think of LT tires this one is sort of out of the box in that all it's designations such as the size and even load range are European/Metric based and don't have a direct conversion to the standards used in the American market so simply lumping it into what we think of as a LT tire is IMO misleading and not accurate. Just the fact that it is a "commercial" tire puts it in a very small category of American LT tires that are meant for commercial use.

I now have 3 road trips totally close to 3,000 miles on my Kumhos and have been pleased with them so far. The biggest downside in these is the lack of universal availability. Of course this is also a negative for the ever popular and tauted Maxxis tires.

Larry
LarryJM
Explorer II
Nov 13, 2013
Lantley wrote:
In the end my experience has been ST tires are inferior. Had all kinds of issues. They ALL magically went away when I upgraded to LT tires. There are many people that tell the same tale. Problems,blowouts,flats with ST's changed to LT tires and all problems solved.
One of the issues that still exist are the tires are marginally rated. The idea that all 4 tires carry equal weight is part of the fallacy. One tire is often overloaded and over stressed from the start. Floorplans are not balance by weight. Why do we expect the tires to carry equal weight?
ST tires are built to marginal/inferior standards vs. and LT. ST tires are not built to a standard that entails transporting humans. They are built and regulated to a cargo only standard. In the end they are inferior. LT's are built for passenger carrying vehicles and are simply a more reliable tire built with better quality control as a result.
LT tire upgrades continue to resolve the blowout issue.

I'm not so sure one can just assume like you have done that there is significant unequal loading on tires on a tandem axle trailer especially side to side. Unless the trailer is being towed in a non level configuration front to back there should be minimal differences in the front and back tires on the same side. As to side to side I have actually weighed my trailer fully loaded side to side and there was only a 50lb difference in the weights and that is for a totaltwo axle weight of close to 7,000lbs. I would think a better assumption for the majority of trailers is they are designed to have a fairly even side to side wt. distribution unless you have significantly modified the insides. I'm sure there are exceptions to this, but I think one can safely assume that there is a fairly good side to side balance in the axle weights for a factory configured TT/5er.

Larry
Lantley
Nomad
Nov 12, 2013
In the end my experience has been ST tires are inferior. Had all kinds of issues. They ALL magically went away when I upgraded to LT tires. There are many people that tell the same tale. Problems,blowouts,flats with ST's changed to LT tires and all problems solved.
One of the issues that still exist are the tires are marginally rated. The idea that all 4 tires carry equal weight is part of the fallacy. One tire is often overloaded and over stressed from the start. Floorplans are not balance by weight. Why do we expect the tires to carry equal weight?
ST tires are built to marginal/inferior standards vs. and LT. ST tires are not built to a standard that entails transporting humans. They are built and regulated to a cargo only standard. In the end they are inferior. LT's are built for passenger carrying vehicles and are simply a more reliable tire built with better quality control as a result.
LT tire upgrades continue to resolve the blowout issue.
gmw_photos
Explorer
Nov 12, 2013
Just to try to clarify, the Kumho is marketed around the world as a van/truck tire. It is marketed in the USA as a trailer tire. A likely guess is that Kumho sees little need to market a LT tire in the US that is a 14" tire, because trucks and SUV's here typically use 16" tires. I would guess the american marketing of this LT tire as suitable for trailers is a smart move on their part as they understand they are offering a high quality tire for the towable market at prices that compare to ST pricing from other providers.

The following quote from the Kumho site in the United Kingdom:
========================

"Radial 857

Modern tyres for people carriers

Excellent driving characteristics in dry and wet conditions
High steering precision
Superb traction
Durable for high mileage
Extremely smooth-running and comfortable
Robust carcass structure
For vans, people carriers and mobile homes"
===========================

....and a pic of the sidewall of one of the 857's on my trailer:
TucsonJim
Explorer II
Nov 12, 2013
spadoctor wrote:
I have trailered over 250000 miles with ST tires and only 1 failure...a US made Marathon. I am one that does not buy into all the BS posted about these tires. Inflate to 10 lbs above sidewall rating...travel at 70 mph all the time...do not hit curbs....ArmorAll 3 times a year...keep covered when not in use and all is good. Some think they know better then the manufacturers and will just b888h because its made in China.(something I personally don't like either but you have your government to blame for that)

And I've had just the opposite lack of success with them. on my 2009 Cougar, I'm on my fourth set of ST tires. All the previous sets were covered under warranty, but not a year goes by that I don't get a serious failure in them. I don't overload them. I use 303 on them every other month, and keep them covered. It's not "b888hing" when you complain about a China-bomb that disintegrates while sitting at rest. I made a post last year about my spare tire that was less than a year old. It was properly inflated and covered with a white tire cover. When it was almost exactly 12 months old, the tire ruptured, blew the cap off and destroyed the spare tire cover. This tire had NEVER been on the road. If it fails just sitting on the FW with no load, then I certainly don't want to trust my life to it.

You've been lucky. If you get a bad batch of Chinese made tires, you'll see the frustration that many of us are experiencing.