Bringing it home...

[twiceblessed....nacole 433]

Question:  If the tread is still good (which is how I judge my car's tires).... why would I replace them because of age?

[h2odivers...Ray 952]

I found an article for you but after I found it it said excludes trailer tires. I'll try to find you a better article.

But basically tires state to dry out and rot. If you look closely at the tires you might see small cracks and this weakens the tire.

[h2odivers...Ray 952]

This was on Popular mechanics website.

Tires do degrade over time, though, and that process is called dry rot. Oils and chemicals in the rubber compound start to evaporate or break down because of UV exposure. The rubber loses its flexibility and begins to crack at the surface, and the structure becomes more and more brittle (think of a really old rubber band), leading to sidewall damage and eventual failure. And we're not talking "Oh, I'll just fill it up and drive on it"; this is a complete loss of function. You might even see tread start to separate. It's good practice to replace tires as soon as you see signs of dry rot, to prevent blowouts and the subsequent loss of vehicle control. Even if there are no signs of rot, the industry standard is to swap out tires before they hit 10 years old, and some tire companies recommend replacement as early as six years after manufacture.

[twiceblessed....nacole 433]

This was on Popular mechanics website.

Tires do degrade over time, though, and that process is called dry rot. Oils and chemicals in the rubber compound start to evaporate or break down because of UV exposure. The rubber loses its flexibility and begins to crack at the surface, and the structure becomes more and more brittle (think of a really old rubber band), leading to sidewall damage and eventual failure. And we're not talking "Oh, I'll just fill it up and drive on it"; this is a complete loss of function. You might even see tread start to separate. It's good practice to replace tires as soon as you see signs of dry rot, to prevent blowouts and the subsequent loss of vehicle control. Even if there are no signs of rot, the industry standard is to swap out tires before they hit 10 years old, and some tire companies recommend replacement as early as six years after manufacture.

 

So, if we inspect the tires and they look sound... do you think we're okay?   I just called Discount Tire and they do install camper tires; maybe I should just have them inspect the tires?  Contacted the previous owner and he had the camper for about 4 years and thought the tires were new we he purchased it from the original owner.  

 

 

 

If LT tires availabe in your weight rating, I would go with them over any ST tires.

 

While ST tires have stiffer sidewalls then LT, the ST construction is usualy cheeper.  The sidewall flex of LT tires help the trailer ride more smoothly then ST. Also, the sidewall flex of the LT tires makes for a nice easy visual check on tire pressure. LT tires are usualy rated for a higher speed then the 65 that ST are rated for. I personaly don't like running tires at  95% of their speed rating for hours on end.

 

 

This is also very helpful because I don't know that I want to keep the tires if they are ST.  We have a decent drive to Disney and even though I can't imagine that we'll go faster than 60 - 65 mpg, I agree with you...running tires at 95% of their speed rating for hours does not sound like a good plan.

[Katman1356...Jason 1,140]

I am by no means no expert but i have been studying on here and elsewhere like crazy but the general rule seems to be 5 years. When i bought our pup i decided to replace right off the bat even though i bought from a fiend and they should have been good for another year. I like knowing exactly when we put them on and i can monitor the changes in them myself from that point. 

 

Maybe it was overkill but i dont want to spend my vacation time on the side of the highway. 

[Grumpy and Grandma 739]

If you go on Michelin ' s Web site they say to have them inspected after 5 years. Depending on how much you use it has a big effect on how long they last. The more it is used the more the oils permeate the tire and it helps them last longer. If it sits a lot they deteriorate faster. Also if you have dual axles LT's do not have the proper sidewall to handle the scuffing in sharp turns, the ST's are designed for that. Forgot to add, don't you think the manufacturer would use LT'S if they were just as safe since they can be bought for less money?<br />

[twiceblessed....nacole 433]

If you go on Michelin ' s Web site they say to have them inspected after 5 years. Depending on how much you use it has a big effect on how long they last. The more it is used the more the oils permeate the tire and it helps them last longer. If it sits a lot they deteriorate faster. Also if you have dual axles LT's do not have the proper sidewall to handle the scuffing in sharp turns, the ST's are designed for that. Forgot to add, don't you think the manufacturer would use LT'S if they were just as safe since they can be bought for less money?<br />

 

Had to look at the pictures again but yes... double axle.  So now I've even more confused.  This trailer business...always seems to pros/cons to every little thing, which is tough for me as I'm a black/white kind-of gal.  Give me the rules, and I'll follow them, type of person :)

 

 

 

 

Maybe it was overkill but i dont want to spend my vacation time on the side of the highway. 

 

I feel that way too....

[h2odivers...Ray 952]

Ok. Here's some more info to help and/or confuse you.

Trailer Tire Facts

Trailer Tire Applications

Trailer tires are designed for use on trailer axle positions only. They are not built to handle the loads applied to, or the traction required by, drive or steering axles.

Inflation

Always inflate trailer tires to the maximum inflation indicated on the sidewall.

Check inflation when the tires are cool and have not been exposed to the sun.

If the tires are hot to the touch from operation, add three psi to the max inflation.

Underinflation is the number one cause of trailer tire failure.

Load Carrying Capacity

All tires must be identical in size for the tires to properly manage the weight of the trailer.

The combined capacity of the tires must equal or exceed the Gross Vehicle Weight (GVW) of the axle.

The combined capacity of all of the tires should exceed the loaded trailer weight by 20 percent.

If the actual weight is not available, use the trailer GVW. If a tire fails on a tandem axle trailer, you should replace both tires on that side. The remaining tire is likely to have been subjected to excessive loading.

If the tires are replaced with tires of larger diameter, the tongue height may need to be adjusted to maintain proper weight distribution.

Speed

All "ST" tires have a maximum speed rating of 65 mph.

As heat builds up, the tire's structure starts to disintegrate and weaken.

The load carrying capacity gradually decreases as the heat and stresses generated by higher speed increases.

Time

Time and the elements weaken a trailer tire.

In approximately three years, roughly one-third of the tire's strength is gone.

Three to five years is the projected life of a normal trailer tire.

It is suggested that trailer tires be replaced after three to four years of service regardless of tread depth or tire appearance.

Mileage

Trailer tires are not designed to wear out.

The life of a trailer tire is limited by time and duty cycles.

The mileage expectation of a trailer tire is 5,000 to 12,000 miles.

Why Use An "ST" Tire

"ST" tires feature materials and construction to meet the higher load requirements and demands of trailering.

The polyester cords are bigger than they would be for a comparable "P" or "LT" tire.

The steel cords have a larger diameter and greater tensile strength to meet the additional load requirements.

"ST" tire rubber compounds contain more chemicals to resist weather and ozone cracking.

Storage

The ideal storage for trailer tires is in a cool, dark garage at maximum inflation.

Use tire covers to protect the tires from direct sunlight.

Use thin plywood sections between the tire and the pavement.

For long term storage, put the trailer on blocks to take the weight off the tires. Then lower the air pressure and cover the tires to protect them from direct sunlight.

Maintenance

Clean the tires using mild soap and water.

Do not use tire-care products containing alcohol or petroleum distillates.

Inspect the tires for any cuts, snags, bulges or punctures.

Check the inflation before towing and again before the return trip.

Keys to Avoiding Trouble

Make sure your rig is equipped with the proper tires.

Maintain the tires meticulously.

Replace trailer tires every three to five years, whether they look like they're worn out or not.

[h2odivers...Ray 952]

More info from tire rack.con

Your trailer is a follower, which often makes tire sidewall flexing a negative. Sidewall flexing on trailers, especially those with a high center of gravity (enclosed/travel trailers) or that carry heavy loads, is a primary cause of trailer sway. Typical passenger radial tires with flexible sidewalls can accentuate trailer sway problems. The stiffer sidewalls and higher operating pressures common with Special Trailer (ST) designated tires help reduce trailer sway.

Also consider that Special Trailer (ST), as well as Light Truck (LT) tires are fully rated for trailer applications. This means ST- and LT-sized tires can carry the full weight rating branded on the sidewalls when used on a trailer.

[h2odivers...Ray 952]

All that being said IMHO I would replace the 4 yr old tires with a good set of LT tires that are rated high enough to handle the weight. Since your probably going to be traveling long distances at speeds in excess of 60-65 mph.

There's a black and white answer. I hope it helps

IMHO the manufacturers probably use ST tires because they have to. You know if they put on LT tires someone will have a blowout (probably do to operator error, I.e. Under inflated tires)

And they'll sue the manufacturer.

[Helmsey......Todd 134]

Another vote for LT tires IF you can find them in your size and load rating. The biggest problem going to an LT tire is finding them in your size. If I had to take a guess you have 15" tires on your hybrid and the selection for LT tires with the weight rating you would need is small. Most people that run LT tires move up to 16" and have a much wider selection to chose from. That is in fact the route we had to go.

I would also not hesitate to deal with Discount tire as they took care of our last 5th wheel when we put new tires (LT) on it. They also put the tires on our travel trailer when we got it (maxxis ST tires) and loved the services from them.

Tires are a touchy subject with the RV crowd..

[arthuruscg 34]

What I don't get is that the forces are not much different between the drive axle of the TV and the trailer.  They both need good traction to stop.  The less traction the trailer has the more stopping the TV needs to do for the entire rig and the longer the stopping distances. Also, with less traction, the trailer would be mroe likely to lock up the brakes.

[Retired and Happy (Ken) 101]

Lots of good info here.  Since we tow a cargo trailer, I had only watched for tire wear, not age or mileage.  And i know we have one ST and one something else (from a flat we had enroute last summer).  The roadside supplier said we should not have a problem due to the relatively low weight of our relatively small trailer.  I guess I'd better check them.  Age and mileage might be a problem on the ST.  And i need to find out what the other one is...after it stops raining.

 

We never did know where the wire sticking from the side of the flat (ST) came from...from inside the tire, or from road debris.

[h2odivers...Ray 952]

What I don't get is that the forces are not much different between the drive axle of the TV and the trailer. They both need good traction to stop. The less traction the trailer has the more stopping the TV needs to do for the entire rig and the longer the stopping distances. Also, with less traction, the trailer would be mroe likely to lock up the brakes.

.

I would say there's different forces in play on a TT and your TV.

1. A tow vehicle has to accelerate putting a lot of strain on the drive wheels. And needs more traction.

2. The front wheels on a car/truck turn were the TT tires don't and will experience a lot more sidewall force as they drag thru a tight low speed turn.

3. A TVs suspension is much different then a TT. A TV needs softer sidewalls to give it a softer ride. If the sidewalls are too soft on a TT it can cause sway. TT needs stiffer suspension to stop this.

[twiceblessed....nacole 433]

All that being said IMHO I would replace the 4 yr old tires with a good set of LT tires that are rated high enough to handle the weight. Since your probably going to be traveling long distances at speeds in excess of 60-65 mph.

There's a black and white answer. I hope it helps

IMHO the manufacturers probably use ST tires because they have to. You know if they put on LT tires someone will have a blowout (probably do to operator error, I.e. Under inflated tires)

And they'll sue the manufacturer.

 

 

Haha... that does help :)   Thank you.... for all of the information you provided.  Super helpful.   :thumbsup2:

[twiceblessed....nacole 433]

Tire size:

 

Currently the tires on the trailer are a 4 ply 14".  Rated for 1750 lbs each at the full 50psi.  Sufficient for our hybrid which is 3700lbs empty.  With this being said, we have two options when installing new tires:

 

Stay with the 14" but go to a 6 ply radial. Price $400 out the door.

OR

Up-size to a 15" 8 ply radial.  Price $615 for the tires and rims. 

 

I believe both are an ST tire (I know the 14" one is).

 

 

Thoughts are which is the better choice?  We have two more trips planned to the Fort this year...each way is about 465 miles.  Next year we'll do at least one trip to the Fort with one more long trip and a few shorter trips.  I'm looking for (obviously) a safe tire with the  smoothest ride possible.

[Helmsey......Todd 134]

Do you know what the gross axle ratings are on your camper, or the gross weight of the camper? I would make sure the weight rating on the tires at least meet or exceed the axle ratings. I looked back and cant see what model camper you guys got so I couldn't look up the axle or gross weight info.

I don't think you would benefit going from a 14" to 15" tire as they would both be an ST tire. If it were me, I would look at the Maxxis M8008 14" tires as they seem to have a good reputation on the RV forums and they can be purchased from Discount Tire (if you have one close). Our fist camper had 13" tires on it and I ran a set of the Maxxis M8008 on it for several thousand miles with no issues while we had it.

 

Man, I need to go back and review some of Larry's posts. I never got to experience him here but am familiar with his work on other forums. Need to make sure I don't turn into that :)

[Command Module...AKA-Brian 8]

Tire size:

 

Currently the tires on the trailer are a 4 ply 14".  Rated for 1750 lbs each at the full 50psi.  Sufficient for our hybrid which is 3700lbs empty.  With this being said, we have two options when installing new tires:

 

Stay with the 14" but go to a 6 ply radial. Price $400 out the door.

OR

Up-size to a 15" 8 ply radial.  Price $615 for the tires and rims. 

 

I believe both are an ST tire (I know the 14" one is).

 

 

Thoughts are which is the better choice?  We have two more trips planned to the Fort this year...each way is about 465 miles.  Next year we'll do at least one trip to the Fort with one more long trip and a few shorter trips.  I'm looking for (obviously) a safe tire with the  smoothest ride possible.

I have a hybrid as well, last year I needed to replace my tires, so I decided to do what I did with our boat trailer and upgrade to a 15", I found a great deal with tires and rims, I put them on and it looked great. The next month we went to a state park about an hour away, every time I turned it felt like the trailer brakes were grabbing, I figured I would look at it went we got to the camp site, well, while I was backing in I had to almost jackknife to get in the site, a guy that was watching me came over and said, you know when you turn the tires go together, I was like what are you talking about, turns out with the semi floating axle on the trailer as I turned the 2 tires on the same side would litterally touch, when I put the tires on I made sure we had about 4-5 inchs between them not realizing when the tires "scrubbed" turning they held each other up, thankfully the tire guy was ok with us returning them for some 14's! The tire guy that was there and acually knew what he was talking about steered me away from LT tires, he said when a trailer turns, the tires do whats called "scrubbing" thats when 1 axle moves and the other just slides or skids on tight turns, with ST tires the sidewall is made to handle this, he said LT tires will end up with a side wall failure, just a couple of things to think about!  Brian