Towmax blown tires

My old Alpenlite came with LT tires on it including the yellow placard on the side said LT tires. Had Goodyear Wranglers on it....

The intent of ST tires was to be better then P tires and they are, unfortunately we have the example like our local rv supply house telling customers that 'there is a fine for using anything but ST tires on a trailer',which I believe stems from - you must use ST instead of P tires on your trailer .
Funny part to the story was the fellow stating, you will be fined for using LT's was standing in front of a Carriage Carri-lite with LT 's on it - what about that trailer I asked ?
Guy did a guppy imitation.

hoopers wrote:

hone eagle wrote:
meagain(chris) and capriracer thanks for all the hard work ,you guys complement each other. I agree wieght is a quick and dirty 'snapshot 'of types of tyres.

Workmanship at the plant is is the roll of dice eh ?

X2

ST tires should be done away with, really. I don't see the point of them, except to save money for the manufacturers. I don't know for sure, but I bet ST tires are just cost and spec reduced versions of normal tires, in an effort to simply save money.

The think the history of them goes back small utility trailers for local use, and somehow they found their way onto large boat, horse and travel trailers on freeways. The result of which this thread was started. Even the largest utility trailer rental company in the country does not use them. Chris

hone eagle wrote:
meagain(chris) and capriracer thanks for all the hard work ,you guys complement each other. I agree wieght is a quick and dirty 'snapshot 'of types of tyres.

Workmanship at the plant is is the roll of dice eh ?

X2

ST tires should be done away with, really. I don't see the point of them, except to save money for the manufacturers. I don't know for sure, but I bet ST tires are just cost and spec reduced versions of normal tires, in an effort to simply save money.

meagain(chris) and capriracer thanks for all the hard work ,you guys complement each other. I agree wieght is a quick and dirty 'snapshot 'of types of tyres.

Workmanship at the plant is is the roll of dice eh ?

steelpony5555 wrote:
Just got back from checking out new 5er's on the lot and it appears that Forest River is trying to make a change in at least their upper level 5er's. I got a brochure for Silerbacks and it shows that up to 10,500 lbs they still use ST tires but after that they use LT tires. Don't know what they did in the past since I know some companies have always used LT tires, but at least on their heavier trailers they know what to use. They still need to change all their 5ers over to LT's.

The Cardinal club gang has be hammering on them for the last couple years. The Cardinals now get wheels rated to 3750 and have the option of GY G614 LRG tires. What you saw was most likely was LT235/85R16LRG Goodyear G614's. I was involved in this, as I did a write up that the head of the Cardinal Club used in face to face talks with them on tire issues. Building large trailers on 7K axles and derating them on the placard to 6750 or 6800 so they can install Marathons rated to 3420 each has lead us to many of these tire threads.

So instead of running around defending ST tires, some of us are doing real work to change the situation. Many of us have been marching in this direction for a number of years! However we continually bump into a lone trooper marching the opposite direction or trying to block movements, and that has slowed our progress. I challenged the Keystone rep with oversight of tires to take the lead on this last year. Now it looks like Forest River is taking it. Others will hopefully follow.

It all boils down to the fact that they are building bigger and heavier 5th wheels that most of the current ST offering cannot handle with their inflated rating, and they fail within the first year or two.

Smart trailer dealers will opt for optional LRG tires on units they floor hopefully. Smart consumers when ordering a trailer will opt of the LRG tires.

Chris

Just got back from checking out new 5er's on the lot and it appears that Forest River is trying to make a change in at least their upper level 5er's. I got a brochure for Silerbacks and it shows that up to 10,500 lbs they still use ST tires but after that they use LT tires. Don't know what they did in the past since I know some companies have always used LT tires, but at least on their heavier trailers they know what to use. They still need to change all their 5ers over to LT's.

CapriRacer wrote:

Let's take this a step further - and compare an ST tire:

7) ST235/80R16 Goodyear Marathon Load Range D - 10/32nds - 34#
8) ST235/80R16 Goodyear Marathon Load Range E - 10/32nds - 38#

Not to split hairs, but!

I do not believe that GY makes the ST235/80R16LRD anymore. And the references I look at state the weight of the LRE at 34-35.4 pounds.

There are a bunch of ST tires that I call the 35 pounders. Towmax, Duro, Mission, Marathon on and on. Then there are the Maxxis and Maxmiler that weigh in at 43.xx(some of the Maxmiler's additonal weight is in deeper tread at 16/32 and wide shoulders).

Now it is the good part!
The Maxxis ST235/80R16LRE weighing 43.43 pounds has 9/32" tread!
The Marathon ST235/80R16LRE weighing 35.4 pounds has 10/32" tread!
(Marathon weight based on phone call to them a few years ago)
Maxxis Diameter is 30.8 and Marathon Diameter is 30.7 based on manufacturers web site specs.




Would you like to start over on explaining the difference between these two very similar tires? Both are rated at 3420 pounds at 80 pounds inflation. Both are poly carcass tires and direct replacements for each other. Yet the M8008ST is 22.7 percent heavier that the Marathon. That is quite a bit more, and can not be written off as tread depth, as the much lighter Marathon wins that one. I suspect one would find most of the difference in the sidewall and casing below the tread. Not many other places to hide the difference. Both of these tires are what some refer to as baseball shaped tires, without wide shoulders. If one looks at the Maxmiler thread going they will see in the pictures I linked there that the Maxmiler looks a lot like an LT tire with wide shoulders that even the manufacture notes in their web site documentation.

Another Marathon weight reference

Chris

Me Again wrote:
Maxxis is not a new kid on the block. They have been around for many years. They have a lot of tire plants in many countries including their Thailand plant that for a long time was the only place that they produced their M8008ST special/service trailer tire.......

Perhaps it wasn't obvious that I was referring to the Maxxis's ST tire as the "new kid on the block". It has only been out there a few years - unlike the Goodyear Marathon and some of the others - and it takes time to develop a full picture of what is going on.

If one has access to more detailed data, then one could construct trend charts, showing length of time in service versus reports of failure factored by the number of tires produced - but we don't have that kind of detail - so skepticism should be the rule when trying to ascertain a particular tire's durability.

joebedford wrote:
In another tire thread, some ... ummm ... person thought it was funny that I thought weight of a tire correlates to durability. When I asked to be filled in on what the joke was, I got no answer.

Anybody care to fill me in on the joke?

So here's the joke:

If you start with a clean piece of paper to design a tire, you can design a casing (the plies, beads, and belts) to be the same, then put different treads on top of that depending on what usage the tire is intended.

Some of those treads are going to be deep (lots of non-skid depth) and some are going to be shallow. Some tread widths are going to be wide, and some are going to be narrow. Some treads are going to be pretty solid (not much in the way of grooves and cross grooves) and some are going to be pretty open (much grooves and cross grooves). Again, it depends on what usage is intended for a tire - and of course, the weight of the tire would vary according to the amount of tread rubber.

I hope it is obvious that with the same casing, the durability would be the same (more or less) regardless of what is happening in the tread. The important thing here is that the casing - which is the key to durability - would be the same, but the weight would be all over the ballpark.

Let's pick a tire manufacturer - Goodyear is a good one because they offer a lot of different tires.

Then look at a particular tire type and size - How about an LT235/85R16.

Tire Rack lists 6 different tires:

1) Wrangler Silent Armor - 16/32nds non-skid depth - 46#
2) WR HT- 13/32nds - 50#
3) WR SR/A - 14/32nds - 43#
4) WR MT/R w/Kevlar - 19/32nds - 52#
5) WR DuraTrac - 18/32nds - 47#
6) WR DuraTrac - 18/32nds - 51#

(Yes, entries 5 and 6 seem to be identical. I suspect there was a recent change and both before and after versions are available, but they have different constructions - meaning differences in casing - but nothing published hints at what those differences are.)

Back on topic: I hope it is obvious that tire weight varies considerably and while the casing may also vary, the difference in weight caused by the casing would be small compared to the differences caused by the amount of tread rubber.

Let's take this a step further - and compare an ST tire:

7) ST235/80R16 Goodyear Marathon Load Range D - 10/32nds - 34#
8) ST235/80R16 Goodyear Marathon Load Range E - 10/32nds - 38#

First, notice that the difference in weights is 4# and that is purely the different in the casing. (OK, there's some rounding taking place here so we need to take that into account) But also notice that 4# is also the difference in entries #5 and #6 above - and that adds credence to my supposition that the difference is construction.

If we try to compare back to the larger tire size listed above (entries #1 through #6), we need to adjust the weight proportionally I'll do it by diameter, since most of a tire's weight is in the tread (31.7/30.7 = 103%), so the weights are adjusted upwards to 35# and 39#. - and if I further adjust the weights to the difference in non-skid depth (10/32nds up to 13/32nds) I get about 45# for the Load Range E - which puts it squarely in the range of the LT tires.

So that's the joke: There is so much variability in tire weights - and quite a bit is caused by differences in tread rubber - that trying to equate tire weight with durability is an exercise in futility.