......tires....

Obewan wrote:
I am a new member but have been lurking for about 6 months so.....at the risk of being kicked out, I have a tire question.

I purchased a new to me 2009 31 foot Keystone Hornet TT in September 2013 and have spent the past months dialing everything in and getting it ready for travel. I was planning on replacing the tires since I don't know their history but today I finally found the date code which is March 2011. There is no evidence of cracking or damage and good tread. I've had no tire problems in the 3000 miles or so that I've towed it so far. The tires are Carlisle DuraTrail 225/75/15.s Load D rated at 2540 lbs. the camper is about 8500 dry and almost nothing loaded (actual weight at scale the day I bought it). I have 2 trips planned in 2014, one of about 2100 miles round trip and one of about 5000 miles round trip and likely smaller more local trips as well.

I have two questions. 1) Is it worth it to replace the tires despite only 2 years and appear in good shape? And 2) should I worry about increasing the load capacity since I'm likely to be near 10000 lbs once loaded. (I will be getting it weighed again before taking off) Carlisle has the same size tire but w 10 ply E rating with 2830 lbs capacity.

Hi,

I'll add a few things and ask a few, What model number camper do you have?

A few things that stick out,

A 2009 trailer with March 2011 DOT date codes, H'mm does your VIN sticker state what the month/year the camper was built? It may have been made in 2009 or 2008. If 2009 and it has March 2011 tires, someone has replaced the tires already. That rings bell number 1...Ding Ding.

You have an actual scaled empty weight of 8,500#? Did we understand this correctly?

You want to load the camper to 10,000# on that size tire. That rings bell number 2...Ding, Ding , Ding....

I had 3 tire failures in mid 2012 and those ST tires same size as yours were made in North America, may have been the last of them too. I was fortunate as I found all 3 by observation and changed them before they let go. You can never look too much at a towed trailer on any part of it.

Your tire size and mine was the same and my camper was sitting just under 10,000#.

Fast Eagle pointed you to the Carlisle site. I see they too now are on board with up'ing the load sizing of trailer tires. Thanks FE.

Carlise wrote:
The combined capacity of all of the tires should exceed the loaded trailer weight by 20 percent.

See lower right on page 1 http://www.carlisletransportationproducts.com/cms_files/original/Trailer_Tires__Tips_Best_Practices.pdf

More reputable tire companies and some high quality RV trailer manufactures are getting on board too with up sizing the tire capacity reserve for the tandem axle application.

I would recommend you do this, load the camper the way you want to up to your 10,000# limit. Head to a truck scale were you can get individual wheel weights. Odds are favorable your tires are "not" all equally loaded. Find that heavy wheel location. Is there 20% or more reserve capacity over the heaviest wheel?

Now you are basing a tire sizing on known actual loads, not speculation. Having new tires on a camper as new as yours may point to the prior owner having failures, or not. It opens up the "why"? But you have no idea how they loaded it, towed it, stored it or even how your loads stack up unless you weigh the rig.

In my case before I changed anything I tried the best I could figure out what went wrong as I'm to the point of being anal about towing, speed, air pressure, covering tires when not used and the weights. In the end I upgraded the tire load capacity. And in my case I also upgraded to 16" LT's. In my case that conversion was not easy due to fender clearance. I worked through it. If that is not an option for you, then ST E load range is the next choice and new rims most likely.

A tire upgrade like this is not cheap, I was not after cheap, I was quality and dependability. Once you have a tire failure, all of a sudden the money issue falls down the list of most important. That said if you are going to put new tires on, go in eyes wide open and know your loads backed by scaled data.

If you want to read up more on this see here

ST225/75R15 to LT225/75R16 Conversion

TT Tire Failure Analysis (Long - Lots of Pics)

Good luck and hope this helps

John