New tires

[Buzzinhalfdozen]

Due to a recent run in with a fence post I got to buy two new tires for my car trailer. So now I have two nearly new load range D tires rated at 2500 pounds and two brand new load range E tires rated at 2800 pounds. I'm thinking I should run one of the new tires on either side of the trailer but I have a few things to ponder on. The trailer is a 20ft 10k pound car hauler that's loaded to max weight quite often.

-Would it matter which axle front or rear. Don't the fronts tend to scrub more on a tight corner?

-Since the LRE has a stiffer side wall and doesn't squish as much will this transfer more weight to the softer tires causing them to run hot?

I'm probably overthinking this but I have tendancy to do that

[IBMobile]

You load the front of the trailer with more weight for control so put them on the front axle.

[diesel4life]

My question would be how old are the old tires and are they ST? ST tires lose 1/3 of their capacity after 3 years and should be replaced. Not only that, they are only rated to 65mph. I've got ST tires on my 14k lb tilt trailer and have had good luck with them but they are getting replaced before summer with a set of LT tires for the above reasons.

[Mopar1973Man]

Like my TowMax ST tires (Loard range D's) on my RV are 5 years old now. Coming due for replacement. Then my BigTex trailer is 2 years old with Maxxon ST tires (load Range C's) as well. No issues with either trailer and limit road speeds well below the 65 MPH limit of ST tires. If you trading up for LT tires watch the specs closely. You might gain on the speed angle but lose on the weight capacity also side wall strength.

[diesel4life]

I'm using a G rated tire so I'll have the capacity. Its going to be more costly but I should get longer service out of them, not to mention I do long distance road trips every year and it sucks being limited to 65ish on a wide open freeway for hours at a time. I'm not looking to break any land speed records but want to at least keep up with traffic and not be a hazard. At 65 I'm getting passed consistently by semis and regular traffic blows by me like Im standing still. I don't like it, so LT tires it is.

[Mopar1973Man]

My last set of Load Range G's were a speed rating of Q (100 MPH) and yes they where ST tires.

http://www.bigotires.com/Tire-Detail/VOMA/SOLID-TRAC-RADIAL-A-S-TRAILER/23024

[diesel4life]

The problem is ST tires just dont have the quality control or the safety standards that LT tires do. They're almost all cheap Chinese made (the ones in your link included). LT tires typically carry a slightly lesser load rating because they are a passenger tire and are derated for safety reasons.

Then like your tires that are 5 years old I've seen ST tire manufacturers claim every 3 years the weight capacity of an ST tire should be reduced by 1/3, so that leaves your tires almost 2/3 less than their original capacity. I will never put enough miles on my trailer in 3-4 years to actually wear a set of tires out (still have 60% tread or more) so it makes sense to me to use an LT tire where at least I won't feel nervous about keeping them past 3-4 years without having a major blow out at freeway speeds.

[Buzzinhalfdozen]

My question would be how old are the old tires and are they ST? ST tires lose 1/3 of their capacity after 3 years and should be replaced. Not only that, they are only rated to 65mph. I've got ST tires on my 14k lb tilt trailer and have had good luck with them but they are getting replaced before summer with a set of LT tires for the above reasons.

The old tires are less than two years old and are ST rated. What's the reasoning is behind an ST losing load capacity after 3 years and an LT won't? They're both a radial tire so the basic construction should be the same. I can see maybe dry rot but not after 3 years. I mean the tires I just bought were made in 2012....

[Buzzinhalfdozen]

Also I did actually look at putting LT on it but not much luck finding any in my size.

[diesel4life]

The construction and materials of sidewalls are much different as well as ST tires have a fraction of the safety standards of an LT tire because they are not a passenger tire. ST tires have a very short lifespan, I bet if you get on the website of the tire manufacturer of your tires you will find the recommendation for replacement every 3-4 years. This is a relatively universal standard among ST tires.

For example, here is a link to Maxxis tires recommendation on trailer tire replacement.

"Trailer tires are not designed to “wear out” like a conventional tire.

“The life of a trailer tire is limited by time and duty cycles,” Maxxis says. “Industry standards suggest that trailer tires should be replaced after three to four years of service regardless of tread depth or tire appearance. On average, the mileage expectation of a trailer tire is typically between 5,000 to 12,000 miles.”

"http://www.tirereview.com/trailer-tire-segment-begins-to-pull-forward-after-downturn/

So being Mike is running on 5 year old Maxxis tires they are at the end of their life without risking a blowout. ST tires are quite well known for blow outs for various reasons including improper air pressure and people assuming because they have plenty of tread left their ST tire is safe to use.

[Mopar1973Man]

So being Mike is running on 5 year old Maxxis tires

 

Not I...

 

RV is running on TowMax ST's and the Utility Trailer is runnning on Maxxon ST's.

[diesel4life]

Like my TowMax ST tires (Loard range D's) on my RV are 5 years old

Correct that is what I was referring to.

I've had decent service out of my current set of Chinese ST tires but the treads are starting to check in a few spots. I dont like the fact that I have to replace them going into their 4th year of service. If I stayed close to home and didn't travel the freeway I might try another year but I'm too paranoid to try it. I don't like the idea of having a blow out on the freeway loaded down. So for peace of mind they're getting replaced.

[Mopar1973Man]

After 5 years the scrubbing has wore the rear tires down. So that why I'm going to replace mine. But I don't buy into the requirement of having to have Maxxis or LT tires for a trailer tires. Like my RV is 15 years old and never seen a blowout during the prevent owner nor myself.

[diesel4life]

But I don't buy into the requirement of having to have Maxxis or LT tires for a trailer tires.

But you run Maxxis tires, no?

Its certainly not required to switch to LT tires. If your OK with trusting a Chinese tire with very few safety requirements and either changing them out every 3-4 years or are comfortable ignoring the manufacturers replacement recommendation then ST tires are fine to use.

The fact that your speeds are substantially under 65 have also probably contributed to the longevity and good track record you've had. The heavy sidewalls of ST tires appears to be the main contributing factor to the increase in temperature they run, combine that with highway speeds and its a recipe for disaster.

[AH64ID]

ST tires, as mentioned, do have much different standards. 

 

Look at two tires of the same size in ST and LT. The LT will be heavier, have a higher speed rating, and a much lower weight rating. 

 

If you are loading to max weight be sure to stick to the speed rating, as most failures occur when loaded heavy or under-inflated. 

 

I am not sure what size tire you run, but the 15" LRE ST options are very limited and most 15" trailer wheels won't support the pressure or weight of a LRE anyhow. It seems that for years LRD was the max for 15" and that's what most wheels were built around. You can find 15" wheels capable of 80psi and 2800lbs, but they are not common. 

 

My trailer came with 225/75R15 LRD ST tires and I wanted to step up to LT's for better puncture resistance. I had to go to 16" rims and get a 225/75R16 in order to have the weight carrying capacity I had with the 15's. 

 

The new wheels and tires are in the bed of my pickup and should get put on the trailer this week. I ended up getting Allied Wheels 870's and Bridgestone Duravis R500's. The 870's are 16x6 and have 3750lbs stamped on the inside of them, and the R500's are rated for 2680lbs at 80 psi. 

 

I wold not call the sidewalls of an ST heavy by any means, they always seem weak to me. My Marathon's in 225/75R15 were 31lbs , and the R500s are 40lbs. There is 1" more diameter, but the section width and aspect ratio are the same so not enough to account for 9lbs (30%) more tire. The sidewalls on the ST's feel flimsy and the LT's are very stiff. 

 

One of the big arguments against LT's on trailers is the stiffer sidewall and the scrubbing in tight turns. 

 

There is zero requirement to go with LT tires, and I have had zero failures on my ST's that are due to the standards/speed. I do tow at 70-72, but not often and never with the tires above about 75% load. The 3 ST flats I have had were due to rock punctures on Idaho's dirt roads. Time will tell if my LT's are better or not, but I do expect them to last longer. My ST's are nearly bald after less than 15K miles and I used 6 of them in a rotation on 2 axles. 

 

 

My last set of Load Range G's were a speed rating of Q (100 MPH) and yes they where ST tires.

http://www.bigotires.com/Tire-Detail/VOMA/SOLID-TRAC-RADIAL-A-S-TRAILER/23024

 

 

Did they say ST on the side or just Trailer? ST trailers by definition are 65 mph rated, and those are clearly not 65 mph rated. ST tires also don't carry standard speed ratings, as there isn't one for 65. 

[flagmanruss]

Interesting discussion.  I've not paid much attention to tires.  I recall my old stock trailer had ST tires.  The expensive horse trailer I still have has bias LT tires...  the maker said they had too many failures of ST radials (back then). 

My toy hauler came with mis-matched ST radial tires, a stack of tire reciepts from the tires that had failed...  and a destroyed inner fender which I had to reconstruct to keep the mice out.  I don't know how heavy loaded they ran or how fast, of course.   I rarely use the Toy Hauler but am concerned about the tires...  The don't appear dry rotted & I have to tow easy anyway.    

I replaced the dry rotted GY ST205/75R15 Marathon tires on my well used enclosed trailer...  My front end guy sold me  Commodore tires in the same size, saying he's had the best luck with them.  I guess we will find out. 

[Mopar1973Man]

Did they say ST on the side or just Trailer? ST trailers by definition are 65 mph rated, and those are clearly not 65 mph rated. ST tires also don't carry standard speed ratings, as there isn't one for 65. 

 

Here you go...I ran these on the truck for 2 years and about 35k miles.

[AH64ID]

Here you go...I ran these on the truck for 2 years and about 35k miles.

 

Yep, not ST tires which is why they have an actual load index and speed rating. 

[AH64ID]

They are on!! I like the look and the 3 miles home the towed GREAT :-)

 

I'll get some better pics down the road, lighting sucks today.

 

 

[Buzzinhalfdozen]

Looking good! Now I'm jealous, I might have to order a set. Are those the same offset/back spacing as the stock wheels?