Tired of ST tire blow outs , going to all LT tires

[3930dave]

Tire sales people say lots of stuff like you have to 'buy new tires every 3 years'. ---Trevor

What's that old line..... "Fool me once...."

I needed some small (by today's standards) trailer tires for an old TT I bought. Based primarily on feedback I got from Diamondpilot, I went with Greenball Towmasters and (knock wood) they have been fine. I'll include the link that helped me with this decision:

http://www.tractorbynet.com/forums/trailers-transportation/229438-decent-non-china-trailer-tires.html

Maxxis was another ST name that came up with good feedback. The other thing I learned was to always run ST's at Max Pressure.

With money no object - setting up a full size modern trailer from scratch, I'd definitely go with LT tires, as there are way too many junk ST tires out there.

The ST tires are bad enough that when I finally need to replace the old P tires I have on my short-haul light utility trailer, I'll likely just buy the heaviest P's I can. Might price Greenballs again, but that means a trip to the USA; Canadian pricing is out to lunch on them.

Rgds, D.

 

[3930dave]

I keep hearing the tire dealers repeat this line, but on the trailers I have replaced with LT I find the LT to actually be stiffer, track better, and have less sway. I don't believe them. I think it is an old rule based on bias ply tires from 50 years ago, not the modern radial tires. Has anyone every considered this: Why don't the mainstream tire manufacturers (Michelin, Firestone, Cooper, Yokahama, Hankook, Perelli, Continental, etc.) produce ST tires? The only one that does is Good Year, and they have a terrible reputation. Is it because they can't make money at it, or they don't want to damage their reputation due to the lower specifications of the ST tires? Most of these companies produce commercial truck tires and other specialty tires (off road, aircraft, AG, etc.), but not ST tires. Makes you think about why not.

You raise a great point. Some of these big suppliers used to make decent ST tires. With today's competition in the market, combined with (IMO) negligently low ST tire specs, many of these big players take the high road and Decline to Participate in the ST market.

The NHTSA seem to look at it as Legally, you can't have people in a trailer rolling down the highway.... so the bar on ST tires is allowed to be set even lower than P tires - again IMO.

All that Mitigated Risk doesn't help you much when a guy blows an ST tire on a 14,000# TT and ends up sideways on the Interstate, right in front of you......

I value the many pieces of good advice I get on TBN, but would have to put ST tires right at the top of that list - so far it has saved me from roadside ST changes.....

Rgds, D.

 

[doxford jim]

I think that there is a lot of hot air blown around trailer tires - most tires in fact.
Changing/renewing tires at three years is just a market ploy to get people to spend money using fear tactics as the means. One could argue that legalities and fear of litigation should a tire fail within the guarantee time is the reason.
FWIW a truck tire will be all I will by now for my trailers. At least I know they work well and by using load range E, I know they will be solid enough to do the job. Funnily enough, I have had more trailer tires suffer punctures than I have truck tire. Only one truck tire problem in hundreds of thousands of miles travelled, yet trailer tires failures after a few thousand miles - hhhhm, something is not right IMHO.

 

[Diamondpilot]

Being in the trailer business part time one of the biggest issues I see with trailer tires is the valve stems. Demand high pressure metal stems. The standard rubber stem is only good to 50 psi. Tire heats up pressure builds then is released by underrated stem causing an under inflation situation leading to tire failure.

Chris

 

[Sprinklerman]

I used to pull a 30' fifth wheel and I have had lots of experience with ST tires...
My rims were 15" on my fifth wheel and 6 lug so I was pretty much stuck with that size...
I ran ST 225 75R 15's...
The best luck I had was with Greenball's...
I always ran max pressures...
I eventually went to E rated tires with a max 80 psi rating...
My rims were only rated to 75 psi so that is what I ran them at...
IMHO ST's do not handle higher tow speeds in higher heat...
Most of the time I was towing my camper was in the summer time and the heat was a factor...
If I was getting another camper it would have 16" rims and I would definitely go with LT E rated tires...
I've blown out plenty of ST's that were in great shape, not old, and properly inflated...
I am not a fan of ST tires...
But I did get a lot of experience in changing them...

My camper came with 6 lug rims also , The FIRST thing I did was get 4 16 in rims , steel and mounted up brand new 16 in lt tires. I have a sunnybrook and the manual recomends LT or ST . Definatly went with LT Load range E

 

[ENC]

We run LTs on all our trailers preferably load range E but we do have one with a set of lighter load range that came off another truck in favor of a matched set but still had some life in them.

 

[CJONE]

I have been switching my trailers over to LT tires with great success. 0 failures so far. I promise you if you run most of these new china ST tires at max ratings you will have failures. I pulled a LT, E tire out of my junk pile and replaced a towmaxx or duromax [can't remember] that had broken cords in a pinch and it is still on the trailer and ran at least 15 degrees cooler than the new Towmax china tire next to it. Has a 3 axle gooseneck that was regularly overloaded with cheap LT E range tires [Kenda cleever I believe] and never had a problem in 5 years or so. Greenball and Maxis are the only one I would even consider but why when the LT's have been perfect. CJ

 

[john_bud]

Isn't the difference the sidewall strength? As I understand it, trailer tires have much stiffer sidewalls to prevent trailer sway. The load rating of the LT tires may be fine, but that doesn't mean they will be stable on the highway. At least that is what I have been told ...........

They do not. Unless SOP has changed, St tires are made with all the left over rubber compound from various runs (car, truck, etc) INCLUDING mis-mixed formulations unsuitable for designated use and all most all inspections / tests are bypassed.

I learned this from people making and inspecting tires. My trailers run lt on heavy trailer and used p on the light 5x10 utility. In the past 25 years I had one tire fail and it picked up a nail.

For me it was a simple decision. I talked to a few of the tire engineers that I know and read the tire requirements in the TRA (Tire and Rim Association Inc.) manuals (About TRA). They define the tire requirements that all the manufactures design to for North America which is why all tire of given type (LT, ST, P metric etc.), size and load range all have the same sidewall rating regardless of brand. The construction differences between an LT and ST tires are minimal. The ST may have more UV stabilizer and a slightly harder rubber compound. Beyond that the radial construction is the same. The big difference is they have lower requirements for speed and duty cycle. They only have to meet 65 MPH speed rating at the max load and have only a 80% duty cycle. The LT has a much higher speed rating (95 MPH to 120+) and a 100% duty cycle. This means that the LT tire must be able to carry the rated load 100% of the time at the higher speed whereas the ST only has to carry the rated load for 80% of the test at the lower 65 MPH speed. The ST may also have a higher failure rate before requiring a recall. These are the reasons that a ST tire of the same size and load range as the LT is rated to carry more. It doesn't have to do it as often or as fast which means less heat over the life cycle. Physics would dictate that the same size tire at the same pressure should be able to carry the same load, but the rules change when the duty cycle and test parameters change giving the ST a higher load rating, but no more psychical capability. This is why I have also been changing all of my ST tire to LT tire with the same sidewall max load capability or higher.

Well put.

 

[3930dave]

Agreed, that was a good post.

I read it the first time it was posted, but for some reason more so today it is striking me as nuts. How the _______ are you supposed to comply with an 80% Duty Cycle ? If you are towing with tires at Max "Rated" Load, do you remove some load every 12 minutes out of a Towing Hour ?

I tend to believe wolfpack2's statement; it goes a long way towards explaining the high real-world ST failure rate...... I'm just thinking that a more practical way to view these contaminated ST "specs" is that the tire # weight rating should be de-rated by at least 20%.

Duty-Cycle makes sense in something like a welder..... on aTire, that's an impractical spec.

Rgds, D.

 

[Sprinklerman]

In my opinion , st tires are great for the local lawn mower guy pulling a couple lawn mowers thru neighborhoods , that sees 55 mph 10 minutes a day . For me , I cant put 20K of assets on china bombs and drive hours at the speed limit especialy in the hot summer