Tire Advice

[uconn_jack]

Hi,

I recently had a blowout on my 2009 Skyline Layton 2970 TT (8,800 GVWR). Bought it used late last year, great shape, with Goodyears (including spare) on it that also looked in good shape and that I understand were about 3 yrs old. Tread-wise they have at least another year to them, and since I am on a bit of a budget, I could just put the current spare into use and get a new spare. However, even being Goodyears, with the blowout I'm not sure I trust the rest and would rather buy 4 new.

I know how most feel about "china-bombs", but I am on a budget so can't go with the Maxxis or Sailuns everyone raves about. Plus I'm not convinced its as big of a problem as its made out to be (my old TT had Greenballs and then HiRuns, never had a blowout until the Goodyears). So anyway, I have narrowed it down to the following tires (ST225/75R15):

Power King Towmax Vanguard - Load Index 117, Load Range E, Speed N
Trailer King RST - Load Index 117, Load Range E, Speed M
Gladiator QR25-TS - Load Index 117, Load Range E, Speed N
Carlisle Radial Trail HD - Load Index 113, Load Range D, Speed M

Now I know Carlisle is the only one of these brands that seems to be acceptable by many, and it is only about $10-15 more per tire than the others, but it does have lower load and speed specs than the others. The Carlisle specs are sufficient for my TT weight, but I am wondering if getting more load buffer with the 117/E tires might be better, despite those tires being held in less regard.

Looking forward to opinions! Thanks!

[JIMNLIN]

what I was getting at with the tire pattern is that if you try to slide a tire with an aggressive side lug sideway that lug will actually try to dig in and fold over rather than sliding (a little bit of exaggeration, as it won't really fold, but you get the point) this helps prevent your truck from sliding sideways when off roading.

True for off roading in soft dirt/mud but not true for hard surface hiway use. Those side lugs have more side slip on hard pavement than a solid rib tire.
The more rubber contact the more friction.
Anyways ST tires come in all types of tread designs from the solid ribs like a commercial ST Sailun S637 or Michelin LT XPS Rib or Bridgestone R-238 solid rib tire.

Off roaders may use a LT tire for their trailers but mostly a mud terrain or a large lug all terrain to keep the trailer on a muddy trail.

Tread rubber compound ?? I've seen nothing from ST tire mfg advertising stating they use a harder or softer rubber tread compound than than a P or LT tire.

Anyways you want a ST or LT or a P tire with less side slip on a trailer choose a tire with larger outside lugs/voids.
If you want a P/LT/ST with less side slip for a trailer choose a tire with solid rib design.

[canoe_on_top]

I changed from Cooper LTs a few years back to Goodyear Endurance STs. All were same size LR E 16 inch. Curious about the sidewalls after reading so much about them I checked them while they were dismounted. The STs had a noticably thicker and stiffer sidewall.That was with each one dismounted on the floor of the tire shop.The difference was significant.I've run STs and LTs over the years. Can't say that I have noticed any difference in towing. With an Arctic Fox, an Equal-i-zer hitch and a Ram 2500 CTD, I just don't have much sway.

[fallsrider]

Huntindog wrote:

aftermath wrote:
I think the "scuffing" comment has to do with the design of the sidewalls not the tread. Because of the lateral pressure put on trailer tires as they are moved into parking situations the ST tire has a stronger sidewall than regular tires.

Actually the opposite is true. Some claims are that STs have thicker cords, but fewer layers in order to run cooler. The same is stated for the shallower tread depth.There has always been a lot of "marketing" claims for ST tires. That is just some of them. It is not in the test...But anyone that has done a hands on of the two types of tires can tell you that the LT has stronger sidewalls.
If you look carefully at the ST construction claims you will see that they have one thing in common. They all make the tire cheaper to manufacture.

What TPMS system do you use?

[StirCrazy]

JBarca wrote:


Hi Stircrazy,

I agree with much of your post; the lack of extra reserve capacity in the tire in a tandem or triple axle trailer setup is an issue direct from some of the RV manufacturers.

And I agree to upgrade a load range to gain more capacity, but not airing up the tire to the max sidewall cold pressure does not give you the full benefit of the upgrade. If you are going to upgrade, you need the extra pressure to gain the benefit to help ward off interply shear.

I may learn something new in this next area, so please explain your thinking. I "thought" I understood you are saying the LT tires with a more aggressive outer tread do not allow the LT tire to slip as much as an ST tire in a turn. Did I paraphrase that correctly? If so, help me understand how you came to that conclusion. Here are my thoughts on why I cannot connect the dots on the tread pattern to hard surface road slip in a dry setting.

I believe we both agree on the friction of the tire tread determines tire slip on the pavement between the tire and the road.

Friction is the main part of the slip equation, and there are only a few ways to change friction on a hard surface road to the tire. Again, I am talking hard surface road, not loose gravel, snow or dirt, mud, etc.

Here is my take based on the friction formulas. To change the friction between the hard surface road and the tire tread contacting the road, these two main variables must change.

1. The weight of the camper pressing down on the road
2. The coefficient of friction between the road surface and the tire tread

There is no variable for tread pattern or contact patch area of the tire in the friction force formulas.

Please help me see your point where the tread pattern changes friction between the tire and the road surface.

I agree with wet, slimy roads, tire rubber compounds, temperature, and the makeup of the road surface. etc. are factors in changing the friction coefficient. Just not sure how the tread pattern on a clean and dry road surface changes the fiction.

On your quest to sort out ST to LT on your camper, yes, sizing is an issue in some cases in finding LT tires rated in the right capacity. I went through the same issue when I had my first set of ST tire failures. I was on 15" ST225/75R15's load range D on a 10,000# loaded camper. After I sorted out what made the ST tires fail, I had 2 choices, upsize to Load range E in ST or jump to 16" and go LT load range E. I ended up going 16" LT load range E. I had to deal with vertical clearance between the top of the tire and the bottom of the camper clearance. I had to modify the suspension setup to get this extra clearance, I could do the work myself, and I'm glad I did. In my case, tire width was not the issue, but vertical clearance. If you want more on this, I did posts over the years on RV.net of each issue and how to overcome it; let me know, and I'll dig them up. And, I went with a highway tread pattern, not AT or other. I did not see any need other than the highway tread pattern in an "on-road" trailer setting.

John

so, the all-important third thing you missed is the actual rubber compound itself. so, ST tires " reportedly" use a different rubber compound which is stronger and stiffer (less grippy) which is why they can carry more weight for the same tire size. so this will reduce the coefficient of friction and when the tire is under shear it will slide on the surface easier. granted we are probably not talking a great deal of difference but enough that it also gets you better gas milage as that rolling resistance (friction) is also reduced.

what I was getting at with the tire pattern is that if you try to slide a tire with an aggressive side lug sideway that lug will actually try to dig in and fold over rather than sliding (a little bit of exaggeration, as it won't really fold, but you get the point) this helps prevent your truck from sliding sideways when off roading. This action acts as a friction modifier and increases the shear. now again small amounts and really, I have never seen a real trailer tire that had agressive side walls, until reading the forum the only people I knew that put LT tires on the rv's were serious off roaders who wanted that extra traction.

I would be interested in seeing what you did to increase the height as I would like to increase mine a couple inches just for a little more box rail clearance.

[StirCrazy]

ya and almost 400.00 a tire up here. I did look at them because they are a commercial all position which there a trailer tire that can be used as steers also. They are taller than mine so I would have to do a bit of modifying. Right now, I am looking at the 637 sailun which are also commercial tires but not all position just trailer, but they come in at 250/ tire up here.

[Huntindog]

StirCrazy wrote:

JIMNLIN wrote:

the tread on a St tire is designed to allow it to scuff sideways easier, as in when you a sharp 90 degree or more turn when backing into a site.

ST tires come with all styles of tread designs (AT types....AS types....and rib type tread patterns) so there is no design attempt for easier side scrubbing.

Rubber treading compounds (hard or soft) has much to do with any tires side slip abilities.

I can't agree with you there, I have been looking at st vs lt tires for 4 years now trying to decide which would be better for my 5th wheel. yes, there are different tread patterns, but the one common Theam of them is the lack of aggressive outside lugs which bite in and resist side movement like LT tires have. this enables ST tires to handle more lateral movment without increased resistance.

plus, another plus for the st tire is they are generally made of different rubber compounds that make them stronger than the equivalent LT tire based on a simular volume of air. Another side benefit of these is they generaly have a lower rolling resistance which equates to a fraction better fuel milage.

the other thing I have found also is to switch to a LT tire the closest thing in size to what I now have (235/80R16 ST) is a 235/85R16 . by switching to this I lose 500lbs (aprox) of capacity per tire.

Part of the biggest issue is dealers generaly put the cheapest tires on the rv's they can get so the weight of the rv is just covered by the tires and sometimes it is less as they assume the hitch weight as not being a load on the tires in some cases. for instance, my 5th wheel came with 10 ply loadmax tires so what I have found the best thing to do would be to just stay the same size in a st tire but go up to a 12ply or even a 14 ply if your rims can handle the higher air pressure requirements. I know a lot of people go to 14 ply then just run them at 90 which is probably fine, but they will run hotter than if they were at 110. When they design LT tires, they have less stiff sidewall and softer compounds, so they handle impacts from road hazards better (ie. potholes) and don't transfer it to the vehicle as much. This is great for a truck, but the downside is less carrying capacity for the same size of tires and more flexible side walls, and better tread grip. When combined with the more agressive tread patterens (usually the addition of shoulder lugs and deeper tread and such) this causes them to grip harder in tight turns which increases the lateral stresses on the belt layers.

the main issue is instead of looking at quality ST tires we are usually talking about switching from China bombs to LT, which ya, that is probably an improvement, but we should really be looking at actually weighing our setups (because we all know how accurate that tally plate is 😉 ) and going with a quality ST tire that has the extra carrying capacity to cover our rigs and some breathing room

LTs are available in MANY tread patterns.Pick one you like.My favorite are Michelin XPS RIBS. One cannot get a more trailer friendly tread pattern. And Michelin recommends them for trailer service.

[trailer_newbe]

I don’t agree with…“just keep them inflated to the proper pressure and you shouldn’t have a problem, no matter what brand”. My 2106 (new) trailer came with china tires and several separated, including the spare with just a few hundred miles. Just got done camping with my neighbors and we found his spare was separated. It was so bad you could see it through the tire cover. His trailer is brand new and this was their 2nd trip. My 2018 trailer (purchased new) came with Endurance tires. They are on the wear marks now and need to be replaced but I’ve had zero issues. We live in the Southwest where it’s hot as hell and the roads suck, so 5 years is really good. Spend the money and avoid road hazards as best as you can.

[JBarca]

StirCrazy wrote:


Snip..

I can't agree with you there, I have been looking at st vs lt tires for 4 years now trying to decide which would be better for my 5th wheel. yes, there are different tread patterns, but the one common Theam of them is the lack of aggressive outside lugs which bite in and resist side movement like LT tires have. this enables ST tires to handle more lateral movment without increased resistance.

plus, another plus for the st tire is they are generally made of different rubber compounds that make them stronger than the equivalent LT tire based on a simular volume of air. Another side benefit of these is they generaly have a lower rolling resistance which equates to a fraction better fuel milage.

the other thing I have found also is to switch to a LT tire the closest thing in size to what I now have (235/80R16 ST) is a 235/85R16 . by switching to this I lose 500lbs (aprox) of capacity per tire.

Part of the biggest issue is dealers generaly put the cheapest tires on the rv's they can get so the weight of the rv is just covered by the tires and sometimes it is less as they assume the hitch weight as not being a load on the tires in some cases. for instance, my 5th wheel came with 10 ply loadmax tires so what I have found the best thing to do would be to just stay the same size in a st tire but go up to a 12ply or even a 14 ply if your rims can handle the higher air pressure requirements. I know a lot of people go to 14 ply then just run them at 90 which is probably fine, but they will run hotter than if they were at 110. When they design LT tires, they have less stiff sidewall and softer compounds, so they handle impacts from road hazards better (ie. potholes) and don't transfer it to the vehicle as much. This is great for a truck, but the downside is less carrying capacity for the same size of tires and more flexible side walls, and better tread grip. When combined with the more agressive tread patterens (usually the addition of shoulder lugs and deeper tread and such) this causes them to grip harder in tight turns which increases the lateral stresses on the belt layers.

the main issue is instead of looking at quality ST tires we are usually talking about switching from China bombs to LT, which ya, that is probably an improvement, but we should really be looking at actually weighing our setups (because we all know how accurate that tally plate is 😉 ) and going with a quality ST tire that has the extra carrying capacity to cover our rigs and some breathing room

Hi Stircrazy,

I agree with much of your post; the lack of extra reserve capacity in the tire in a tandem or triple axle trailer setup is an issue direct from some of the RV manufacturers.

And I agree to upgrade a load range to gain more capacity, but not airing up the tire to the max sidewall cold pressure does not give you the full benefit of the upgrade. If you are going to upgrade, you need the extra pressure to gain the benefit to help ward off interply shear.

I may learn something new in this next area, so please explain your thinking. I "thought" I understood you are saying the LT tires with a more aggressive outer tread do not allow the LT tire to slip as much as an ST tire in a turn. Did I paraphrase that correctly? If so, help me understand how you came to that conclusion. Here are my thoughts on why I cannot connect the dots on the tread pattern to hard surface road slip in a dry setting.

I believe we both agree on the friction of the tire tread determines tire slip on the pavement between the tire and the road.

Friction is the main part of the slip equation, and there are only a few ways to change friction on a hard surface road to the tire. Again, I am talking hard surface road, not loose gravel, snow or dirt, mud, etc.

Here is my take based on the friction formulas. To change the friction between the hard surface road and the tire tread contacting the road, these two main variables must change.

1. The weight of the camper pressing down on the road
2. The coefficient of friction between the road surface and the tire tread

There is no variable for tread pattern or contact patch area of the tire in the friction force formulas.

Please help me see your point where the tread pattern changes friction between the tire and the road surface.

I agree with wet, slimy roads, tire rubber compounds, temperature, and the makeup of the road surface. etc. are factors in changing the friction coefficient. Just not sure how the tread pattern on a clean and dry road surface changes the fiction.

On your quest to sort out ST to LT on your camper, yes, sizing is an issue in some cases in finding LT tires rated in the right capacity. I went through the same issue when I had my first set of ST tire failures. I was on 15" ST225/75R15's load range D on a 10,000# loaded camper. After I sorted out what made the ST tires fail, I had 2 choices, upsize to Load range E in ST or jump to 16" and go LT load range E. I ended up going 16" LT load range E. I had to deal with vertical clearance between the top of the tire and the bottom of the camper clearance. I had to modify the suspension setup to get this extra clearance, I could do the work myself, and I'm glad I did. In my case, tire width was not the issue, but vertical clearance. If you want more on this, I did posts over the years on RV.net of each issue and how to overcome it; let me know, and I'll dig them up. And, I went with a highway tread pattern, not AT or other. I did not see any need other than the highway tread pattern in an "on-road" trailer setting.

John

[Huntindog]

Thermoguy wrote:

Huntindog wrote:
See my post on page 2.

Apparently I missed page 2 when I first read this and then decided to add my $.02. Nice write up and thanks for taking the time to research this. Sort of agrees with my own experiences in trying to decide which is better for my trailers. Since they fall well within the load rating of the LT I will stick with that for my use. My only tire failure ever was an ST tire.

I can't take credit. It is an old post by IIRC SeinorGNC. He did all the research. When it was originally posted all of the links to back up the article worked. Over time websites have changed. It is still legit info though.
It is interesting though, over the 30 plus years I have been towing RVs how little has changed. ST tires are still a problem. And yet they continue to have their proponents. Watching the masses chase after the newest entry to the market thinking it is the solution is like watching the Lemmings charge off a cliff.

[Thermoguy]

Huntindog wrote:
See my post on page 2.

Apparently I missed page 2 when I first read this and then decided to add my $.02. Nice write up and thanks for taking the time to research this. Sort of agrees with my own experiences in trying to decide which is better for my trailers. Since they fall well within the load rating of the LT I will stick with that for my use. My only tire failure ever was an ST tire.

[manley]

ktmrfs wrote:

manley wrote:
For what it’s worth, I replaced all four of my 3-year old Endurance tires with Hercules strong guards yesterday. Having lost confidence in the GY bombs, I figured I couldn’t be any worse off with the new (Chinese) tires than with the old (American) ones. The reviews that I found on the Hercules tires and brand were decent. We will see as time will tell.

what issues or problems were you having with the Goodyear Endurance?

Had one separate completely and do pretty bad damage. Manufacture date code “0720” and inflated (religiously) to 80 psi. No uneven wear, and no signs of impending failure. I bought those (and paid a premium) to avoid those kind of problems.

[coloelk]

Get your trailer axles aligned and you'll see what is causing 95% of your tire issues.

[JIMNLIN]

Thermoguy wrote:
The reason I ask is because when I was looking to buy my last set of tires I asked a couple of different shops about LT vs ST. Everyone said buy ST for a trailer, but when questioned, they all admitted that ST tires are not tested the same as a vehicle tire. They don't have the same standards and don't have to perform like a vehicle tire. Since you don't ride in the trailer, you don't have the ride experience that you expect in a car or truck. Fortunately, my trailers fall within the weight range that I can use an LT tire and that is what I choose. But, just thought since this is such a controversial topic on these threads, to ask, how are they tested?

clicky link

The info huntingdog posted comes from this thread by seniorGNC back in 2009. Hot topic on rv webstires back then per FMVSS testing required by all tire mfg and their road tires and puts to sleep all the false opinions that some how the ST is superior to the LT tire for trailer use.

[ktmrfs]

manley wrote:
For what it’s worth, I replaced all four of my 3-year old Endurance tires with Hercules strong guards yesterday. Having lost confidence in the GY bombs, I figured I couldn’t be any worse off with the new (Chinese) tires than with the old (American) ones. The reviews that I found on the Hercules tires and brand were decent. We will see as time will tell.

what issues or problems were you having with the Goodyear Endurance?