I've searched the thread(s) and haven't come across anything yet that helps me out, yet. I've got a 34' 5th wheel currently wieghing 10,500 when we're road ready. It has a max of 12,000 so that could be a possibility to carry more since I have the new 2011 6.7L pulling it.

I've had the Max King OEM tires fail within one year, and of course there's no way to get any warranty help. So I switched the last three over to Marathon tires because I've run them for 15 years on two other campers. Now they are blowing out, ...... I'm finding out they are made in China and have lost any good reputation they ever had.

Looking today at 4 or 5 dealerships/tire stores they all have recommended the Carlisle tire. I have now ST225/75R15 in a D load (2540 lbs). This Carlisle would be the same size but an E load (2830 lbs).

My two questions are:
1. Has anyone had a good long run with these, or know factually they have been a real good tire?
2. I've heard ST is only good to 65 mph, the tire store called their Carlisle distributor and said there is no speed rating like that on these tires. Anybody ever heard that or can contradict that?

Right now I'm looking at a set of 5 for out the door price of $760, and they're made in Ohio and South Carolina.

 

I have read several unfavorable reviews on Carlisle tires over the years, I would not use them. They have been referred to in the past as china bombs, (same for all tires made in China). I would not use them, the damage they do and possibility of serious injury just isn't worth it in my opinion. A few dollars more for a safer tire experience is well worth the extra $$$$.
Here is a link on some reviews Carlisle Radial ST Utility Tire Reviews. Buying Guides & Consumer Product Reviews - Epinions.com

 

If you want to run faster than 65 then you need to switch to a LT tire.

Always make them E-rated.

I had regular Goodyears on my last TT. Just a truck tire since I had 16" rims.

My current 5er came with ST's. I am running them a couple of years then I will switch as well.

 

I totally agree, I use Michelin XPS RIBs LT 16's, quite a few prefer the LT's over ST's. There are some raging tire wars on some of the RV forums (over brands and ST vs LT. I think if you could change to 16 in LT tire you would be safer.

 

Some RV manufacturers are selling their products with LT tires on them instead of ST's. Mine came with LT's:

 

2540 x 4 = 10,160 < this is basically your problem

2830 x 4 = 11,320 < this is a step in the right direction

But you will want to check your rims and make sure they are rated for an 80PSI tire. If they originally had 65PSI tires mounted, they may only be rated for that pressure. Personally that does not bother me at all, but tire shops may refuse to mount them for you. Just remember that if you put an 80PSI tire on a 65PSI rim, you have not increased the load capacity of those rims. But you have increased the safety margin of the tires when carrying the original load.

I would skip the Carlisle and find a Maxxis tire dealer. Maxxis may be the best ST tire out there. As far as I know, ALL ST tires are rated 65MPH maximum, even the few 15" LR-E available.

If you really want to be done with tire problems, stepping up to a 16" LT tire will get that done, but it gets expensive and you have to be sure you have wheel well clearance for that.

 

My placard calls for LT tires too.
Supporting rims and clearance would also be necessary. "Maxxis may be the best ST tire out there". Dollar for Dollar

 

Just checked my sticker, My 5'r came with Carlisle LT tires. I recently put on a set of "E" rated BF Goodrich commercial T/A's. I've had good luck with em on my truck.
I always thought LT meant "Light truck" I guess not.

 

It does mean that. But that doesn't mean you cannot mount them on trailers.

BTW, ST means Special Trailer.

 

I found this, Its what made me wonder.
I'm not saying that I agree with it, just never knew what they are claiming


•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.
Inflation•Always inflate trailer tires to the maximum inflation indicated on the sidewall.
•Check inflation when the tires are cool and have not been exposed to the sun.
•If the tires are hot to the touch from operation, add three psi to the max inflation.
•Underinflation is the number one cause of trailer tire failure.
Load Carrying Capacity
•All tires must be identical in size for the tires to properly manage the weight of the trailer.
•The combined capacity of the tires must equal or exceed the Gross Vehicle Weight (GVW) of the axle.
•The combined capacity of all of the tires should exceed the loaded trailer weight by 20 percent.
•If the actual weight is not available, use the trailer GVW. If a tire fails on a tandem axle trailer, you should replace both tires on that side. The remaining tire is likely to have been subjected to excessive loading.
•If the tires are replaced with tires of larger diameter, the tongue height may need to be adjusted to maintain proper weight distribution.
Speed
•All "ST" tires have a maximum speed rating of 65 mph.
•As heat builds up, the tire's structure starts to disintegrate and weaken.
•The load carrying capacity gradually decreases as the heat and stresses generated by higher speed increases.
Time
•Time and the elements weaken a trailer tire.
•In approximately three years, roughly one-third of the tire's strength is gone.
•Three to five years is the projected life of a normal trailer tire.
•It is suggested that trailer tires be replaced after three to four years of service regardless of tread depth or tire appearance.
Mileage
•Trailer tires are not designed to wear out.
•The life of a trailer tire is limited by time and duty cycles.
•The mileage expectation of a trailer tire is 5,000 to 12,000 miles.
Why Use An "ST" Tire
•"ST" tires feature materials and construction to meet the higher load requirements and demands of trailering.
•The polyester cords are bigger than they would be for a comparable "P" or "LT" tire.
•The steel cords have a larger diameter and greater tensile strength to meet the additional load requirements.
•"ST" tire rubber compounds contain more chemicals to resist weather and ozone cracking.Storage
•The ideal storage for trailer tires is in a cool, dark garage at maximum inflation.
•Use tire covers to protect the tires from direct sunlight.
•Use thin plywood sections between the tire and the pavement.
•For long term storage, put the trailer on blocks to take the weight off the tires. Then lower the air pressure and cover the tires to protect them from direct sunlight.
Maintenance
•Clean the tires using mild soap and water.
•Do not use tire-care products containing alcohol or petroleum distillates.
•Inspect the tires for any cuts, snags, bulges or punctures.
•Check the inflation before towing and again before the return trip.
Keys to Avoiding Trouble
•Make sure your rig is equipped with the proper tires.
•Maintain the tires meticulously.
•Replace trailer tires every three to five years, whether they look like they're worn out or not.
Trailer Tire Warranty
•The Carlisle trailer tire warranty applies to the original purchaser for three years from the date of purchase or until the tread depth reaches 3/32".
•The OE (original equipment) warranty goes into effect at the time of the trailer purchase

 

Well, we all mount LT tires on our trucks, so I don't understand why they are saying that. Perhaps they don't think their (Carlisle) LT tires are a good choice for cars/trucks. Don't know.

 

It's a bit misleading.
Perhaps Carlisle makes a LT tire specifically for trailers.?
My 5'r sais that it came with LT tires, but there is also a sticker that sais "Carlisle tires and wheels"
I guess we are missing something.

 

I very rarely use 4 letter words to describe anything... Carlisle tires are JUNK I cannot recall the brand that I put on my boat (trailer) several years ago- But I will check later this week. There have been similar discussions in this forum in the past and the resounding advice is to get a LT tire with an E rating. Good luck

 

I have Goodrich LT 235/86/16E on my 5er The load rating is 3084 lbs per tire @80 psi. I have the same tires on my truck. Something to remember is 15% to 20% of the trailers weight is on the rear wheels of the truck, ( tongue weight ) Also the axle weight is 6000lbs each axle, but again the weight on the axles are reduced by the tongue weight. My trailer weight is 12,100 lbs dry and 14000 loaded and ready to go. my trailer tongue weight is 2245 lbs loaded. real close to the max axle weight and the max tire weight rating. I have had problems with ST tires in the past, separation and blow outs. I have about 14000 to 15000 miles on the LT tires with no peoblems. Im sold on LT tires. I just got home this past Monday from a 2400 mile trip to New Mexico with no problems and no worries. just my .02

 

I should have clarified in my original post.
My GVWR is 12,000 lbs
Road ready it's 10,500
Hooked to the truck the two trailer axles weigh 8,620 pounds. D load range by the book is fine it just appears the Tow King (OEM tires) and Marathons have both let me down.

I may look for some LT tires (real highway truck tires) in D load 15" and see where that takes me.