Flogged to death but require info on tires

I switched to LT for the tread puncture strength.

I never had a "china bomb" failure of my ST's but I did have several low speed punctures on slow gravel roads.

I've had LT's for two seasons and I am very happy with them.

Since ST tires have IMO an unrealistic load capacity for todays RV usage LT type tires effectively have a margin built into their stated load capacity rather than a "negative" margin seen in ST type tires. If you follow the load limits for LT tires you will probably see better performance and more reliability from your tires.
Keystone seems to be demonstrating better engineering practices.

If they are GoodYear they also come under the name G614 RST.

What brand LT?

I would replace those tires asap. Then send a letter to Keystone and ask them WTH they are doing.

Wow, Keystone really screwed up I guess and put LT's on my trailer from the factory. Why would they do that when ST's offer all the advantages I just read about here? I guess I will get them pulled off soon and replaced with the tire so many say should be on it. LOL

SprinklerMan wrote:
Tires are a big circle , they are designed to roll , and carry weight . They have ratings . I have never seen a LT tire that says light truck use only , I have seen ST tires say " Not for passenger use " . The LT tires on my trailer dont know they are on a trailer or truck .They hold weight and they roll . The main difference between the 2 is how long they last and how fast you can drive

Sidewall stress ? Unless you are flying down a 30 MPH off ramp at 60 MPH the trailer doesnt experience any more sidewall stress than the tow vehicle.

Wonder where you ran the Finite Element analysis to back up your claim about sidewall stress.

If you google "Interply Shear tires" you can read some technical papers that explain why tires have belt separations and why tires in RV trailer application see belt shear forces that are 20% higher than when on a motorized vehicle.

It isn't the sidewall stress that results in tire failures. Sidewalls suffer Run Low Flex Blowouts from the air leaking out. or they suffer belt separations from lower design standards and much higher belt forces dues to trailer application.

rbpru wrote:
The information I stated is still factual. The fact that some TT manufacturers use LTs reinforces my statement. That is, manufacturers use the type of tires they believe is suitable for their intended application.

As was noted, LTs are usually found on high end TTs, representing a small portion of the TT market. Their reasons for using LTs is known to them but one can assume that LTs were selected to meet the TT maker's design criteria.

Volumes can and have been written about why some manufacturers choose LTs over STs. Suggestions include everything from superior performance, to feeding the vanity of the anticipated buyer. All of which is just conjecture as to why they were selected.

If one feels safer on LTs, for what ever the reason, that is what they should buy.

If one prefers a higher load rated tire, they are available.

Since many people do quite well with the OEM tires that came with their TT, I do not expect a major shift to LTs any time in the future. But, as always I could be wrong.

I would be more inclined to trust the tire selection made by RV companies if they were willing to stand behind their decisions. Anyone get a multi-year tire warranty from the RV company when they bought their RV? or did the tire warranty end when you drove off the sales lot.

Huntindog wrote:
As usual, whenever this topic comes up... An ST fan will make all sorts of excuses as to why ST tires fail, such as curbing, over speeding, under inflating, the sky is blue etc.. Then smugly proclaim that those who had ST tire failures simply did not understand the limitations of the ST tire design... And that when used within their limitations they will give good service.


To that I say that many of us DO understand the ST tires limitations. We DO understand the much lower testing standards for the ST tires, and we find those limitations.......... Well, limiting.
There is no logical reason why an ST tire on a TT should have to be babied so that it doesn't fail. We feel that the TT follows the TV, and its tires don't fail at anywhere near the rate that the ST tires do. No matter how we drive it.
As for the "new" Carlise ST tires now being sold... Maybe they will pan out... But this is the same company that for many years told us how great their previous ST tires were... I am not interested in experimenting with my money on their tires any more. Fortunantly for Carlise, there is a new batch of consumers that are eager to believe and spend their money on them. I wish them well, and hope that they have better luck than many of us have had.

But remember this. The ST tire testing standards are what they are.
And the LT tire testing standards are what they are.
.
This link to the govt. testing standards tells it all.
Tire testing standards

If you don't want to read the test details just think of this.

ST load formula was based on single axle trailers running 50 mph. The test standards for ST tires are from the early 70's. LT tires are tested to latest, newer 2002 standards.

IMO if you drive no faster than 55 on a 13' RV then St might be right for you. :-)

I do not understand where the idea of ST tires have stronger sidewalls comes from. The tire sidewall retains the pressure. If two tires have the same Load Range (ply rating) and are rated for same psi 80 psi for example what data would indicate one is "stronger" than the other?

The tire sidewalls do not carry the load. If that were true we would not have sidewall failures when a tire looses air.
It is the air pressure that supports the load. Load Inflation charts support that concept.