Carlisle Trailer Tires

[Food Scientist]

Hi

I know in the past the Carlisle tires had gotten a bad rap so when I went to buy some trailer tires, I was going to get some Maxxis tires. I bought some Carlisle tires instead (83 vs 130 for the Maxxis) at Discount Tire, which the sales guy said that these had been completely redesigned and tested. I bought the 13 dollar warranty just in case as I was going on a long trip (over 4000 miles total).

The tandem 3500 lbs per axle trailer had 4400 lbs on the way down and 5200 lbs on the way back, so the tires were not fully loaded but neither was I nearly empty.

I hit plenty of pot holes and even ran the trailer off the road at one point in time going through a construction zone. I never did have one problem with the tires (although I did run these in cooler weather) even 300 miles at a time. Time will tell how well these tires hold up over their life but so far so good.

 

[c502cid]

What country where they manufactured in?

 

[Ken2]

Do you have a spare trailer wheel & tire? If you have one tire fail and run much at all on the single remaining good tire on that side, plan on replacing both after overloading that one.

Check the valve stems often. Some of the tire failures are due to valve stem failures. Check the tires often for inflation pressure and any sign of bulges or serious cracking.

Did you balance the new tires? For unknown reasons, trailer tires are rarely balanced, and some are way out causing them to bounce down the road until they fail. If they were balanced on the usual cone on the balancing machine, is the center pilot hole in the wheel actually in the true center of the wheel? One way to check is to jack up the wheel and spin it by hand. Look at the pilot hole and see if it is rotating eccentrically. Any decorative cover might have to be removed. If the pilot hole isn't in the true center, the wheel must be mounted on the balancer using the tire shop's lug-centric adapter...if they have one. Or, use Dyna Beads inside the tires for balancing. I use them on the motorcycle, truck, & trailer in addition to the usual balancing, and they do smooth out the ride.

 

[weebl]

What size, load range and application is the tire for? Good chance you could go with an LT tire instead. Much better pricing, selection, quality and longevity over the ST [censored] that's sold. Many trailers are now OE equipped with LT tires.

 

[CapriRacer]

Part of the problem with trailer tires is loading.

It is common for trailer manufacturers to underestimate the actual load carrying ability of their trailer. Compared to cars, trailers have a much higher loading profile.

Personally, I like to see a 15% overcapacity for tires on trailers.

BTW, for as long as I can remember - and that's a long time! - LT tires have been used on trailers. They seem to suffer the same problems ST tires do. Nevertheless, I wouldn't hestitate to use an LT tire in place of an ST.

 

[Food Scientist]

Originally Posted By: c502cid
What country where they manufactured in?


China

 

[Food Scientist]

Originally Posted By: Ken2
Do you have a spare trailer wheel & tire? If you have one tire fail and run much at all on the single remaining good tire on that side, plan on replacing both after overloading that one.

Check the valve stems often. Some of the tire failures are due to valve stem failures. Check the tires often for inflation pressure and any sign of bulges or serious cracking.

Did you balance the new tires? For unknown reasons, trailer tires are rarely balanced, and some are way out causing them to bounce down the road until they fail. If they were balanced on the usual cone on the balancing machine, is the center pilot hole in the wheel actually in the true center of the wheel? One way to check is to jack up the wheel and spin it by hand. Look at the pilot hole and see if it is rotating eccentrically. Any decorative cover might have to be removed. If the pilot hole isn't in the true center, the wheel must be mounted on the balancer using the tire shop's lug-centric adapter...if they have one. Or, use Dyna Beads inside the tires for balancing. I use them on the motorcycle, truck, & trailer in addition to the usual balancing, and they do smooth out the ride.


I plan to get a spare tire before the next trip (I had one that came with the trailer but not the same size). Tires were balanced. When I spin the tires freely while on the hub they spin concentrically.

 

[Food Scientist]

Originally Posted By: weebl
What size, load range and application is the tire for? Good chance you could go with an LT tire instead. Much better pricing, selection, quality and longevity over the ST [censored] that's sold. Many trailers are now OE equipped with LT tires.

ST205/75/R15 Load Range C (about 1820 lbs per tire) Application: trail tire

I read that ST tires are better for trailing than LT tires for a couple of reasons:
1. Are rated for holding a heavy load for long periods of time
2. Have more plies in the size walls for impact resistance
3. Have a different rubber compound to resist UV light decaying the tires

Big Tex (who manufactured the trailer) still puts on ST tires according to their website of the same size and load range as mentioned above. I did read however that anyone who is serious about trailering does away with 15" tires altogether and puts 16" rims and Michelin XPS Rib tires.

 

[bullwinkle]

In the old days LT tires were what trailers came with-both my boat trailer & brother's dirt track car trailer have ANCIENT 7.00 LT bias trailer tires on them (15" boat, 14" car)-going to have to put ST tires on them because the old LT trailer tires aren't available anymore. I can state from experience (co.'s enclosed) that the ST radial trailer tires aren't very strong-although the Carlisles have outlasted the Power King and Freestar ones.

 

[weebl]

Originally Posted By: SVTCobra

I read that ST tires are better for trailing than LT tires for a couple of reasons:
1. Are rated for holding a heavy load for long periods of time


LT tires would be too. A heavy vehicle is a heavy vehicle, whether it's a truck or a trailer.


Originally Posted By: SVTCobra

2. Have more plies in the size walls for impact resistance

Possibly. I don't know. CapriRacer is the expert and I'm sure he can say. I suspect that this isn't a blanket statement you can apply across the board.

Originally Posted By: SVTCobra

3. Have a different rubber compound to resist UV light decaying the tires

I have heard this too, along with a compound designed to sit idle for long periods better than LT tires. That is the theory, anyway. From a practical perspective, you have this standard more in tune with a trailer's needs, however, you get for the most part, ST tires made by a second tier brand at best (save Goodyear). No R&D money sunk into this market. Manufacturing in China for 99% of these. Poor quality control. High failure rates. Speed limited to 65 mph, leaving little to no margin for safety on the highway.

Or there are the LT tires. From a load perspective, they are almost the same as an ST tire. Sure, you lose the advantages that exist in theory. CHoose a good brand/model (and there are quite a few), and you gain, a market where there is ongoing R&D, the availability of tires made outside of China, many made in the USA or Canada. Good quality control. Failure rates that are much lower compared to ST. Speed ratings on many of these, giving you a safety margin.

On top of that, you get better availabiliy, often better pricing and mostly radial choices. The UV resistance? Cover your tires during storage. Besides, what about all the light trucks these are mounted on? They see the sun too. And these need to be replaced in a 6-10 year time frame anyway, whether they are ST or LT. Idle for long periods? So you have "square" tires for the first few miles after a long park, big deal. And if you tow lots, those are moot points anyway.

For me, the replacement choice is very clearly going to be an LT tire.

 

[CapriRacer]

OK, it might be time another installment of my famous lecture series on tires (My lectures are famous, aren't they? ....well, AREN'T THEY???)

- and today's topic is ST tires.

"ST" stands for "Special Trailer" - and typically they are sized using old sizing systems or obsolete sizes in current systems. For example, you will find 7.00-15ST's (old sizing system), F78-14ST's (another old sizing system), or our current topic: ST205/75R15 (an obsolete size in the current sizing system)

Why? This is a way to use old molds.

What is illuminating into how this works is where there are tires available in both ST and LT sizes - like 235/85R16's.

An ST235/85R16 Load Range E has a load carrying capacity of 3640# at 80 psi, and has a speed limitation of 65 mph (unless accompanied by a speed rating)

An LT235/85R16 Load Range E has a load carrying capacity of 3415# at 80 psi (single) and is also speed restricted to 65 mph (unless accompanied by a speed rating)

- BUT -

Typical LT tires carry a Q or R speed rating and if you back calculate load carrying capacities vs speed rating you'll find that ST tires and LT tires are the same. And as you would guess, they are frequently built out of the same materials.

So, No!, they don't have more sidewall plies, and No!, they don't typically have more UV protection. Needless to say, this can vary - making it difficult to say this is an absolutely true statement.

I think most of the problem with ST type tires is:

1) Trailer manufacturers typically under-estimate the payload capacity on their trailers.

2) Trailer manufacturers typically use the minimal tire size for the rated load.

3) Trailers are commonly operated at speeds higher than 65 mph.

4) Trailer manufacturers are very cost driven.

5) The cost factor keeps the more highly technical tire manufacturers away.

6) ST tires are not on the cutting edge of technology.

7) Many of the tire molds used for ST tires have built in deficiencies.

And the list goes on.

I am of the opinion that when ST tires for trailers are sized, there needs to be a 15% unused capacity - a lesson learned from the Ford/Firestone thing a few years back.

I would not hestitate to use LT tires on trailers - and I would try to use the largest tire that will fit under the fenders (without scraping).

 

[Food Scientist]

I appreciate everyone's input, but as I mentioned in the original post anyone who uses a trailer all the time would go to 16" rims and Michelin or other name brand tires. All this post was for was to mention that the redesigned Carlisle tires held up pretty well for 4000 plus miles with a decent load.

 

[friendly_jacek]

Another issue with ST tires is age as they rarely used. One of my Carlisle tires catastrophically blew out last year. I looked at the date code and it was exactly 8 year old. It had little weathering as tires were covered. I quickly replaced the other tires as they were equally old.

I also abused the tires pulling a fully loaded trailed at 70-75MPH. I need to stop doing that.

 

[Ken2]

The 65 mph speed limitation on ST tires is the best kept secret in the business. At one time I saw a chart showing the necessary load reduction for speeds above 65 (I think the chart was from Goodyear), but I can't find it now--maybe it's gone. Any motor vehicle or combination motor vehicle plus trailer over 10,000 GVWR cannot exceed 60 mph on any highway in the state of Washington--another well hidden secret. http://apps.leg.wa.gov/rcw/default.aspx?cite=46.61.410
(Buses on a scheduled route can run 70 on roads so posted for cars--the same bus on a charter is limited to 60!)

For 15" tires there are just about no LT tires that will handle the load that ST tires claim to handle. If the brake drum has six studs, and if there is room for the bigger tire, 16" wheels and LT tires can be used. Otherwise the cost of new drums must be added to the cost of new tires & wheels to make the change. There might be a 15" XL tire that carries more load than a particular 15" ST tire, and the charts say that the max load rating on the non-ST tires needs to be reduced 10%. Among 16" LT tires, the Michelin XPS Rib steel cord LT235/85R16/E seems to be the pick of the litter. The Goodyear G614 RST Load Range G trailer tire in that size is rated to carry 3750#@110 psi.

I recently reshod a small utility trailer that has 12" wheels. I chose to use passenger car tires instead of Carlisles. The passenger tires have a weight rating well above the capacity of the trailer plus its own weight.