Tire Expert Needed

[Roy W.]

I need to pick someone's brain about tires. My travel trailer weighs 9200 lbs loaded, with 8200 lbs on the axles. (Flying J CAT scale) It came with 225/75R/15 8 ply load range D tires which gave me a lot of trouble (Marathons). Two years ago I switched to another brand (Denman), same size, but upped them to load range E (10 ply). For two years they worked flawlessly and I had finally settled back into my comfort zone while traveling. On my last 3000 mile trip, I had tread ply separations in three of these 10 ply tires, one of which blew tearing up a wheelwell. The tires have always been run at 80 psi, parked up off the ground, and covered. Alignment is not an issue.

I'm now at a complete loss as to what is causing this. The load range D tires should have carried 10,000 lbs and the 10 ply should have carried 11,000 lbs, so with 8200 lbs on the axles, I'm way over on load carrying capacity.

I special ordered this trailer with shock absorbers on all four wheels. I'm suspicious that they may be too stiff and not dampening the usual interstate bumps and pot holes and that maybe the tire is absorbing all the shock, causing the problem.

Before you recommend going to a 16" LT tire (I have room) keep in mind that the only thing they are going to give me is increased carrying capacity, and I have all of that that I need.

[mfire1339]

Are you driving a tad over the speed rating of the tires?

Mike

[Hitchhiker]

What does Denman Tire say? I saw in their website catalog that their tires are warranted for 60 months.

[450Donn]

First problem, the tires are only rated for 65 MPH.
Second problem, they are ST tires!
To really cure the problem you need to go to a quality LT rated tire in 16 inch size and be done with it!
Almost all of the ST rated tires are/were made in China. There tons of threads and posts on the subject. None of them positive except to say that they are positive that you will have problems, and positive the repairs will be expensive when they do blow.
Switching to a 16 inch wheel will allow you to buy tires almost anywhere in the US, Canada or Mexico. You will be able to shop for the best price on a quality tire, and that price will guaranteed be a lot less than any ST tire you put under the trailer.
One last thought/question. What is/was the date code on the tires that you are now having problems with? My guess when you bought them they may have been old stock.

[Roy W.]

My interstate travel speed is 60-65. Never exceed 65 mph. The tires are dated the 27th week in 2007. I bought them in August 2007. That makes them pretty new. I wrote Denman directly before I went back to my tire dealer as I am asking for reimbursement of my insurance deductible. My dealer looked at the tires and said he would warranty them with out any trouble, but I'm not sure I want the same tire back. Waiting to hear from Denman.

[FastEagle]

Did you actually have a certified tire tech inspect the tires? I'd like to know his thoughts as to the cause of the thread seperations.

FastEagle

[Roy W.]

My tire dealer (independent,not a franchised store) has been in the business for 20 years and knows his tires backwards and forwards. He just shakes his head when I show him the tires. He says he has people hauling bulldozers around on those same tires without any problem. No word from Denman yet.

[sknight]

Are all four dated the exact same? If so it could be as simple as a quality control issue that week.

[Roy W.]

Yes, all four tires are dated the 27th week of 2007 and I purchased them in August 2007. Strange that they went for 2 years and maybe 10,000 miles before they started coming apart.

[sknight]

For three of four to come apart at the same time means that either a common weak link in the tires reared it's head or something changed on your rig, and unless you suddenly doubled your weight or started getting really violent with curbs (Which I doubt.) I'm going to lean towards an internal flaw.

The only outside possibility I can see would be running over something in the road, but to damage three of four would be very unlikely.

[JimmyDee]

Quote:

Originally Posted by 450Donn First problem, the tires are only rated for 65 MPH. Second problem, they are ST tires! To really cure the problem you need to go to a quality LT rated tire in 16 inch size and be done with it! Almost all of the ST rated tires are/were made in China. There tons of threads and posts on the subject. None of them positive except to say that they are positive that you will have problems, and positive the repairs will be expensive when they do blow. Switching to a 16 inch wheel will allow you to buy tires almost anywhere in the US, Canada or Mexico. You will be able to shop for the best price on a quality tire, and that price will guaranteed be a lot less than any ST tire you put under the trailer.

I did exactally this. The 16" tires have been on for about 2 years. It cost a bit but my dealer purchased the old 15" rims from me. These tires hardly get warm at highway speeds. Anything I was ever told about using LT tires on a trailer, just wasn't true. If I purchase a new trailer, the 16" tires will be a necessary transfer to the new trailer. I'm using 225 -16 tires and replaced 225-15 tires.
Jim

[FastEagle]

So, you actually have more than 10,000 miles on them. The normal life expectancy for the ST tire is 3-5 years for age. And 5-12,000 miles for usage. Some newer ST tires boast of a 22,000 mile usage range.

FastEagle