Tires

[Byron Kinnaman]

Originally Posted by alan in alberta

This might be a good topic after 30,000 kms or so.

If it has too much air the middle of the tread will be worn and if not enough the outside edges will be worn.

ready ...set ....get camping

I'll be waiting for the results .....lol

That may be true for automobile and truck tires that get a lot of tread wear. Single axle trailer trails don't wear the tread out. I replaced mine after 5 years (somewhere around 30,000 miles) and there no noticeable tread wear. Current tires have well over 20,000 miles in two years, tires look brand new.
The way to tell if the trailer tires are under inflated is that unmistakeable sound of a blow out and melted tires.

[Jim Bennett]

Originally Posted by Brian B-P

I have noticed that Escape uses ST205/75R14 tires on all trailer sizes (4 of them on the heaviest models, the 19' and 21' models) while Scamp uses "13” C load radial" (ST185/80R13?) on all models... even the 19' which would overload those tires by over 500 pounds per pair at GAWR. It does not surprise me that the two companies might have different approaches to tire inflation.

My tires are rated for 1,760 lbs at 50psi, and that is where I run them. Times four, that is 7040lbs capacity. Should hold my trailer up fine....just sayin'.

[Jim Bennett]

Originally Posted by Byron Kinnaman

Current tires have well over 20,000 miles in two years, tires look brand new.

Pretty much where mine are at now, distance and appearance wise too. Four years old now, seems a shame to change them next spring, but I will.

[Byron Kinnaman]

Originally Posted by Jim Bennett

Pretty much where mine are at now, distance and appearance wise too. Four years old now, seems a shame to change them next spring, but I will.

I know the feeling. After all these years of looking at the tread on automobile tires now we have to look at the date instead for the trailer.

[gmw photos]

Originally Posted by Jim Bennett

Pretty much where mine are at now, distance and appearance wise too. Four years old now, seems a shame to change them next spring, but I will.

In my mind, all the more reason to buy tires that are better than ST. As in LT or commercial.
As far as I can tell, ST tires are, simply put, "built down to a cost", and part of why they can be, is because they don't carry passengers. Having said that, I have been told by a tire engineer ( a man I trust what he says ) that even though ST tires don't necessarily "have to" meet the same standards as tires rated to carry passengers, most of them "would pass" those standards.
The trouble is, it can be hard to suss out which ST tires are good vs those that are cheap charlies that are ready to fall apart immediately.
It seems that among the ST tires, Maxxis 8008 are developing a pretty good reputation.
GoodYear claims on their site that a Marathon at three years should be derated in load capacity by 30% if I remember the number correctly. For me personally, that is just unacceptable, when I can buy a reasonable alternative.
As a real general trend, I would say you owners of FGRV's probably have fewer tire failures simply because your trailers weigh less.
Again, y'all buy what you want, I know where I am directing my dollars on this subject.

[honda03842]

George,

I've used Goodyear Marathons for the last 6 years and we are now on our second set. We have never had a failure and are on the road 7-11 months a year with a fair percentage on rough roads.

Goodyear's warranty is for four years. I have never read that they need to be derated by 30% after 3 years. As a user I would appreciate it if you could document this claim. I have not found that statement on their RV tire site, one that is well worth reading in its entirety.

Goodyear RV Tires

There are various guides and FAQ on this site. For people who do not use their tires frequently, there are many good suggestions on how to maximize tire life.

I found the following particularly interesting because we are people who regularly use our tires and this promotes longer life.

• Usage per year - more frequent usage will result in longer life
• Vehicle storage practices (6 months loaded with little or no rotation is not good!)
• Usage in warmer climates can also impact a tire's overall life due to greater extreme ozone exposure

Like everyone else on the site I do not want a tire failure on my trailer. I pay careful attention to them including the mounting of tire pressure and temperature sensors.

Goodyear Marathons have worked for me.

[Carol H]

Norm raises a good point regarding tire life. Personal experience with current trailer using a set of LT's and ST's is they have failed long before the tread showed much sign of wear. In both cases there was no blow out - simple tire inspection while getting gas showed they were starting to crack badly between the treads & had I carried on there was a good chance they would come apart very soon. In both cases the tires had been checked by a tire shop prior to the trips and balanced and deemed to be fine. I also do check the air pressure often.

In the case of the LT's they were on the trailer about 4.5 years. In the case of the ST's they were on the trailer 3 years and 3 months. In both cases I was on long trips and the problem was noted in an area with *very* limited options as to what they could be replaced with - one tire shop towns and the next town a great distance away. So no option but to take what they had on the shelf, not possible to choose a different brand/type.

In both cases the tire shops that did the change overs suggested that one should not expect a tire trailer to last nearly as long as a car tire for the simple reason trailers tend to sit for much longer periods of time than car tires. If sitting out in the sun in one spot they will be subjected to a higher amount of UV damage in the spot the sun is continually hitting - which was the case for the LT tires that were on the trailer when I purchased it - the trailer had been sitting for 2 years or more in the Idaho sun with very little use. Another cause I was told that if sitting in a damp climate in one spot they will start to root out from the inside. I live on the wet coast so that may have been part of the issue with the ST's that replaced the LT's.

Based on the above I am not going to leave a set of tires on my trailer any longer than 4 years and will start shop around at home where I have more options as to what to replace them with once they hit 3 years of age regardless of how good they look.

Thats just been my experience with tires in recent years and I am not a tire expert. I know there are people here who have gotten a lot more years out of their trailer tires and lots of suggestion as to why.

[gmw photos]

Originally Posted by honda03842

George,

I've used Goodyear Marathons for the last 6 years and we are now on our second set. We have never had a failure and are on the road 7-11 months a year with a fair percentage on rough roads.

Goodyear's warranty is for four years. I have never read that they need to be derated by 30% after 3 years. As a user I would appreciate it if you could document this claim. I have not found that statement on their RV tire site, one that is well worth reading in its entirety.

Goodyear RV Tires

There are various guides and FAQ on this site. For people who do not use their tires frequently, there are many good suggestions on how to maximize tire life.

I found the following particularly interesting because we are people who regularly use our tires and this promotes longer life.

• Usage per year - more frequent usage will result in longer life
• Vehicle storage practices (6 months loaded with little or no rotation is not good!)
• Usage in warmer climates can also impact a tire's overall life due to greater extreme ozone exposure

Like everyone else on the site I do not want a tire failure on my trailer. I pay careful attention to them including the mounting of tire pressure and temperature sensors.

Goodyear Marathons have worked for me.

I'll have to dig for it Norm. It is a tech service bulletin to dealers, which is generally not east to find on the net, but it's there. I used to have the document saved, but I think it got lost/deleted when I bought a new computer last year. I'll look for it later.....need to head down to the barn right now, will be away from the computer for the next 8 hours or so.

george

[gmw photos]

Originally Posted by Carol H

Norm raises a good point regarding tire life. Personal experience with current trailer using a set of LT's and ST's is they have failed long before the tread showed much sign of wear. In both cases there was no blow out - simple tire inspection while getting gas showed they were starting to crack badly between the treads & had I carried on there was a good chance they would come apart very soon. In both cases the tires had been checked by a tire shop prior to the trips and balanced and deemed to be fine. I also do check the air pressure often.

In the case of the LT's they were on the trailer about 4.5 years. In the case of the ST's they were on the trailer 3 years and 3 months. In both cases I was on long trips and the problem was noted in an area with *very* limited options as to what they could be replaced with - one tire shop towns and the next town a great distance away. So no option but to take what they had on the shelf, not possible to choose a different brand/type.

In both cases the tire shops that did the change overs suggested that one should not expect a tire trailer to last nearly as long as a car tire for the simple reason trailers tend to sit for much longer periods of time than car tires. If sitting out in the sun in one spot they will be subjected to a higher amount of UV damage in the spot the sun is continually hitting - which was the case for the LT tires that were on the trailer when I purchased it - the trailer had been sitting for 2 years or more in the Idaho sun with very little use. Another cause I was told that if sitting in a damp climate in one spot they will start to root out from the inside. I live on the wet coast so that may have been part of the issue with the ST's that replaced the LT's.

Based on the above I personally I am not going to leave a set of tires on my trailer any longer than 4 years and will start shop around at home where I have more options as to what to replace them with once they hit 3 years of age regardless of how good they look.

Thats just been my experience with tires in recent years and I am not a tire expert. I know there are people here who have gotten a lot more years out of their trailer tires and lots of suggestion as to why.

Carol,
I am curious, what were the LT tires you had ? It's generally hard to find LT tires in diameters smaller than 16" in the US market. Kumho, Hankook and couple of others are available, but they can be hard to locate.

george

[honda03842]

Under FAQ/Technical Goodyesr has a statement about the difference between LT tires and ST tires.

Goodyear RV Tires

[Roy in TO]

Originally Posted by Brian B-P

What the first item tells me is that I should not take the second item seriously.

You lost me Brian, I don't initially see any corelation.

Now cany anybody explain what the difference is when it comes to ST and LT tires? I don't mean LT for light truck either. Knowing this might make some of the other comments make more sense.

[Francesca Knowles]

Originally Posted by Jon Vermilye

Well, the trailer now has a set of Maxxis D rated ST205/75/15 tires

What did the tire guys say about the wear pattern on the old tires? (picture from this thread you posted about them).

Did they have any concerns re. camber/toe in etc?

Francesca

[Jim Bennett]

Originally Posted by honda03842

Under FAQ/Technical Goodyesr has a statement about the difference between LT tires and ST tires.

Goodyear RV Tires

This is what is said there without going looking. This advise seems sound to me, and is what I would do because it works.

_____________________________________________

What is the difference in a trailer specific tire and regular passenger tire?

Trailer tires are considered a special category in the current global design standards of Tire and Rim. The major difference is that trailer tires are required to carry 10% more load than an equivalent P-metric size tire. LT type tires are actually on a lower formula and would require a significant size or load change to meet the trailer load requirements.

In the design process, we evaluate what works best under trailer applications/conditions. We typically find that a narrower tread width and a shallower non-skid (tread depth) provides a better overall performance in a free rolling position. This is one case where wider is not better. There are significant design differences with these tires and this explains why trailer tires are in a special category. In addition, that is why we recommend using trailer designed or trailer specific tires in trailer towable applications.
__________________________________________

[Jim Bennett]

I do have to wonder, would car tires have the same 5 year recommended life too. I don't think I have ever had a vehicle that went more than 2 or 3 years without requiring the tires to be changed.

[Francesca Knowles]

Originally Posted by Jim Bennett

(quoting Goodyear)
We typically find that a narrower tread width and a shallower non-skid (tread depth) provides a better overall performance in a free rolling position. This is one case where wider is not better. There are significant design differences with these tires and this explains why trailer tires are in a special category. In addition, that is why we recommend using trailer designed or trailer specific tires in trailer towable applications.
__________________________________________

Of interest may be the fact that these same principles govern the design/selection of tires put on big long haul trucks. That industry has spent many dollars researching this question, particularly as it relates to fuel economy. Tires for semitrailers are designed by very similar parameters as ST's.

Here's a link to a tire selector for big truck/trailer tires- note that wheel position is the second question asked. Tire selector

Francesca

[Jon Vermilye]

Originally Posted by Francesca Knowles

What did the tire guys say about the wear pattern on the old tires? (picture from this thread you posted about them).

Did they have any concerns re. camber/toe in etc?

Francesca

Well, according to both the trailer shop & the tire shop, the wear was normal for a torsion axle, although might show some signs of slight under inflation. I'm not going to argue with them, but every under inflated tire I've ever seen shows wear on both the inside & outside, not just the outside. They are a shop that services many torsion axle trailers. They were surprised that 2 year old tires were worn out until I mentioned that they had around 33,000 miles on them.

I am going to try running the Maxxis 8008 tires at sidewall pressure & see what happens...

[Francesca Knowles]

Interesting...

Well, they're the experts!

My torsion-equipped Trillium's on its third set since I bought it and wear has been pretty even...but I have replaced them much sooner, based on age/miles rather than visual wear so maybe that's why.

Francesca

[Roy in TO]

Originally Posted by Jim Bennett

Trailer tires are considered a special category in the current global design standards of Tire and Rim. The major difference is that trailer tires are required to carry 10% more load than an equivalent P-metric size tire. LT type tires are actually on a lower formula and would require a significant size or load change to meet the trailer load requirements.
__________________________________________

Wow!
Thanks for quoting that Jim.

Who would think that? I assumed that by buying trailer tires for my trailer I'd have something better suited than car tires.

Requires a signifant size or load change. Shoot.

[Roy in TO]

OK, from the same link I posted before, I see an explanation.
http://www.carlisletransportationpro..._Practices.pdf

– An "LT" designation, when shown on a trailer tire size specifies load

range only, it is not designed for use on light trucks.

– ST tires generally offer approximately 10% percent more load
capacity than a similar LT tire and nearly 40% more than a P

passenger tire.

What I don't know in the last quote is where the LT refers to truck tires or trailer tires.

[Francesca Knowles]

Originally Posted by Roy in TO

I assumed that by buying trailer tires for my trailer I'd have something better suited than car tires.

.

You would.

And better suited than LT tires, too. Since they form an integral part of vehicle suspension, LT's design parameters include an important component for passenger comfort, just like P-tires. Softer ride doesn't equate to better performance on a trailer.

Francesca