Could This Be The Solution

[SteveH]

The solution to our tire problems? A 235/75 15 LT tire in load range D.

Pirelli Scorpion ATR

It's called an On/Off road, all terain tire, but that mostly describes the tread design, and I wonder if this would in any way prevent it's use in trailer service.

Pirelli is a well respected tire manufacturer, it's an LT tire in load range D, so it should handle the weight OK, it's a 15" so no need to replace wheels. They are a little more expensive than ST tires, but who wouldn't be willing to pay a little more for a tire that would carry the weight and stay together?

[handn]

I think this tire would work well for my 25 Safari.
Maximum load of the tire is about 2225 pounds. I like one tire to be able to carry the entire load on one side in case of a blowout. On my Safari GVW is about 6000 pounds. Subtract the hitch weight and this tire comes close to meeting the test.
I would be concerned about using this tire on a heavier double axle Airstream like a classic or bigger Safari. In that case, I would go to 16 inch wheels or use an E rated ST tire.

[Wayne&Sam]

What is the maximum psi on that tire?

[Ahab]

It's not designed for TT use.

[silverleeper]

Originally Posted by Wayne&Sam

What is the maximum psi on that tire?

The web site states max load as 2335 lbs and the max inflation as 65 psi.

[SteveH]

Originally Posted by Ahab

It's not designed for TT use.

That's right, and those that are designed for trailer use (ST), are no good. People who are using LT (Light Truck) tires, are having much more luck with the tires actually staying in one piece.

[aftermath]

Please enlighten me. What makes an ST better for trailer applications? I know that they are designed for trailer use but what is the actual problem with running LTs?

[silverleeper]

Originally Posted by aftermath

Please enlighten me. What makes an ST better for trailer applications? I know that they are designed for trailer use but what is the actual problem with running LTs?

Take a look here. Trailer Tire Facts - Discount Tire

[barts]

Originally Posted by aftermath

Please enlighten me. What makes an ST better for trailer applications? I know that they are designed for trailer use but what is the actual problem with running LTs?

ST tires are built w/ heavier sidewalls, supposedly; they are also sometimes of bias ply rather than radial construction. In the past (1970s) , Airstream has supplied their trailers with LT radial tires; many of us run them today, as quality standards appear higher for such tires than for tires aimed at the very cost-sensitive trailer market. It appears to me that ST tires are a means for delivering the sturdy tire carcass needed for trailering w/o the other expenses associated with tires aimed at the LT market. Most trailer tires become rotted with age/ozone rather than worn out due to use, in contrast to what happens w/ LT tires.

Like many contentious subjects here, you'll find lots of opinions on this topic. Personally, we run LT tires on both the truck and trailer. When folks complain about the rate of tire failure w/ ST tires on their heavier Airstreams, several people recommend switching to 16" LT load range E tires. I'll likely do this when we need tires again, even though our 'stream isn't very heavy.

If you're worried about trailer tire failures, install a pressure monitoring system; this will prevent the most common source of failures - undetected leaks leading to overheating. There's a reason these are now mandatory on new vehicles.


- Bart

[SteveH]

Originally Posted by silverleeper

Take a look here. Trailer Tire Facts - Discount Tire

I do not take Discount Tire's Trailer Tire Facts as the Gospel, because in the first paragraph there are some statements that are just wrong:

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.
• An "LT" designation on a trailer tire size specifies load range only. It is not designed for use on light trucks.
• Do not mount "ST" or "LT" trailer tires on passenger cars or light trucks.

An "LT" designated tire IS designed and intended for use on a Light Truck.

"LT" tires are supposed to be mounted on Light Trucks.

[silverleeper]

Originally Posted by SteveH

I do not take Discount Tire's Trailer Tire Facts as the Gospel, because in the first paragraph there are some statements that are just wrong:

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.
• An "LT" designation on a trailer tire size specifies load range only. It is not designed for use on light trucks.
• Do not mount "ST" or "LT" trailer tires on passenger cars or light trucks.

An "LT" designated tire IS designed and intended for use on a Light Truck.

"LT" tires are supposed to be mounted on Light Trucks.

It is just information. Take what you what from it and leave the rest. What can you consider "Gospel" these days? Someone is allways trying to spin info to suit themselves or there bottom line. All a person can do is research and make the best choice for the situation that is in front of them. Good Luck!

Google LT vs ST tire. LT vs ST - Google Search

Would I run LT tires on a trailer? Maybe, If I need to.

Would I run ST tires on a truck? Not likely.

[SteveH]

All this tire searching on my part is driven by two things....the fact that people are continuing to have lots of trouble with "ST" tires, and a friend of mine found two Goodyear Marathon tires with tread seperation on his '07 25' Airstream. As far as other apearances, the tires look like new, and he estimates the tires have about 10,000 miles on them, max, and have never been run low on air pressure.

This type of premature tire failure is in my opinion, totally unexceptable.

I find it interesting that the minimum speed rating for any tire sold in the USA for any vehicle that carries human passengers is 87MPH, yet tires for a trailer pulled by a passenger hauling vehicle has tires rated for only 65MPH.

[Bob Thompson]

Considering the 65mph rating for ST tires, even the self appointed experts seem to get it wrong. See: How to Choose the Right Camper Tires & RV Tires

Where they say this about ST tires:

Camper and trailer tires are stamped with "ST" on the sidewall. The 'Special Trailer' (ST) tires are constructed for better high speed durability, extended towing time and damage resistance under heavy loads.

What are they thinking?

[Ahab]

"the fact that people are continuing to have lots of trouble with "ST" tires" is not a fact. There is no evidence to support that statement, only hearsay. If there was, the National Highway Safety Administration would have stepped in a long time ago.

[SteveH]

Originally Posted by Ahab

There is no evidence to support that statement, only hearsay. If there was, the National Highway Safety Administration would have stepped in a long time ago.

Ahab,

You obviously do not read all the threads on this forum about trailer tire failures, and I submit to you that my friend who found two GYM's on his '07 Airstream with seperations this weekend, is evidence enough for me.

And, the NHSA couldn't care less about trailer tire failures because nobody's pink little body is riding in them.

[slowmover]

Originally Posted by Ahab

"the fact that people are continuing to have lots of trouble with "ST" tires" is not a fact. There is no evidence to support that statement, only hearsay. If there was, the National Highway Safety Administration would have stepped in a long time ago.

We don't know. And considering the performance of FEMA with KATRINA, or the MMS with DeepWater Horizon, I wouldn't lay any bets about the responsibility of the Feds just because the statutes or laws say they should.

My take on ST tires is that they are cheap (they are, in price), that they're meant to hold up to years of sitting around by design, as well as having a pretty decent weight rating If, in fact, they are REALLY the ideal choice, I'd like to see some reasonable proof . . LT tires look better on many counts.

To the OP: I quit buying PIRELLI tires years ago due to customer service after the sale (warranty). I'd be careful about that aspect with any brand, but especially so with this one.

tires for a trailer pulled by a passenger hauling vehicle has tires rated for only 65MPH.

This is not absolute. See the GOODYEAR Marathon .pdf. They are good to 75+ in some situations (pressure/load dependent).

Good luck.

[bmklawt]

I see a lot of people saying LT tires are only for light trucks.
This is what is molded into my tire's.
"Goodyear 7.00-15LT Travel trailer Hi-Miler"
Just FYI.

[Gene]

Government regs for speed, wear and temperature are for passenger tires, not LT or ST tires. Some LT tires have been speed rated, but I don't believe it to be required. Thus a manufacturer may state something, but whether it's accurate is not known.

Now some light trucks and SUV's come with P (passenger) tires and some come with LT tires. It may be that what was once called LT are now called P for some reason.

You have to look beyond LT, P, and ST to know what to do. Lots of info is on retailer websites and manufacturer websites about tires.

Gene

[mwells4654]

Ok - every time these tire threads come up I get more confused.

Now my question -

If you do not like the GYM's because of the D load range and you want something to carry more weight, hence load range E, why not go with a load range E 15 inch tire and forgo buying 16 inch wheels? I do not mind putting money into my TT but it is not a bottomless bucket.

Safety should be a big portion of anything you do in life and buying tires for your beloved TT should be no excepton. Is it because the other tires are an unknown?

I found three different brands in a quick search showing 225-75-15 load range E. I know they will not carry as much as a 235-75-16 load range E but is the approx. 700lbs. difference (15's 2830 - 16's 3500) necessary. Isn't a load range E tire much more stiffer than a load range D? Airstreams want a soft ride (that is why there is so much written about the axles) and now when we get to the part where the trailer meets the road we stiffen her up. This is what gets confussing.

I understand, as it seems, that there are more problems with ST GYM's than other brands, IMHO it is because that, more than likely, there are more ST GYM's running down the highway. I don't know and I am sure this debate will be covered more and more as time goes on. But for what it's worth I have had my say.

I still do not know which tire I am going with but unless there is some very convincing data to back it up, I am going to stay with 15 inch wheels. Not the ones I currently have (originals I think) in the spring - new axles - wheels and tires. I will get off my box now.

Have a great Columbus Day weekend.

[SteveH]

Originally Posted by mwells4654

Ok - every time these tire threads come up I get more confused.

Now my question -

If you do not like the GYM's because of the D load range and you want something to carry more weight, hence load range E, why not go with a load range E 15 inch tire and forgo buying 16 inch wheels? I do not mind putting money into my TT but it is not a bottomless bucket.

Almost all failures of the GYM's is not due to tire carcass failure (unable to carry the weight), it is because of tread seperation first, the tread being thrown off the tire, then the blowout.

Going to a load range E tire, would not help the problem in any way, unless you ran them at 80 lbs of pressure, and that would only make them run a little cooler. There are many people on here that won't even run the LR D's at 65 lbs because they want a soft ride.

I have a friend in our unit that recently had two Carlisle LR E's fail from tread seperation. I have another friend in our unit that recently found two, three year old GYM's with seperated treads on his trailer, fortunately before they failed.

The problem is, all ST tires are junk. That is my opinion, and I've been told the same thing by two different tire retailers. Then, one of them will not install anything but an ST tire if he knows it's going on a trailer because of liability reasons.

Our problem is as I see it, there are no LT tires made in 225/75 15 size. There are a couple of 235/75 15LT's made and a few 700/15, and one 7R15.

When my trailer tires need replacement next time, I will go to a 15" LT tire.