......tires....

......If the tires show no signs of degradation I would continue to use them until the first signs of a problem........snip

The problem here for the OP is this "first sign of a problem" may well be side of the road, changing a destroyed tire, with traffic zooming by a couple feet away.

To the OP, to quote Inspector Callahan, "do 'ya feel lucky punk ? Well, do ya" ?

I have two numbers and two letters for you. 16". LT.

That is all. Carry on men.

If you are a bit uncomfortable with the tires , sell the old ones on craigs list to some landscaper who uses his trailer local , use the money to ofset the price of a new set , I prefer LT tires but thats another story . ( 30 ft sunnybrook 10K gross)

FastEagle

If the tires show no signs of degradation I would continue to use them until the first signs of a problem. Inspect them religiously including the tread area for any signs of cracking and monitor air pressure at each use. I personally would not replace them with anything but Maxxis brand M8008 radials if you continue to use ST tires, preferably in the E range tires.

The other thing that kills ST tires aside from overloading is speed. ST tires are rated for 65mph and running too fast heats them up as much as overloading them does. I would say keep the tires at only 3 years old, as you can usually get 5 years out of a set without too much trouble. However, if the original owner ran them overweight or overspeed, they could be ready to pop. According to the tire experts that post here (we actually have a few posters who have spent their careers in the tire business) damage from overloading and overspeeding is cumulative and irreversible, and generally is not evident just by looking at the tire. If the original owner was not a very good driver, the tires could also have internal damage from curbs, etc. Bottom line, you can't really tell much just by looking at the tires.

I wouldn't replace them for date alone, but I would consider starting with a fresh set if the budget allows. The problem with a blowout is that it can really damage the TT when the tire comes apart, and rip out gas lines, water lines, and wiring in the process. Damage potential varies by mfr, some use sheet metal inside the wheel wells and are careful not to route plumbing and electric too close to the tires, others use plastic wheel well liners with wires and pipes just above and in harm's way. Check your TT when you get a chance and see how it's constructed and how likely you are to suffer damage from a blowout.

Consider adding a TPMS for the TT tires. Many blowouts start as slow leaks, the tire heats up as the pressure drops until it blows. If you can catch the leak with the TPMS it gives you a chance to pull over and fix the problem before the tire self destructs. I use a Dill TPMS but there are many good systems available.

You can't tell tire pressure just by looking at the tires since they run in pairs on each side of the TT. I rented a dual axle cargo trailer from U-Haul last year to move my daughter back to NJ.

We packed that thing full and decided to check tire pressure before we left. All tires looked fine, but on the right side the front tire was 65psi, the rear was at 0. Had a nail in it. It didn't look flat because the front tire was holding the trailer up, and that front tire surely would have blown from overloading had we ran it down the road like that. (I plugged the tire and all was well.)

E rated tires only buy you capacity if the rim is rated at 80 psi. At 65 psi, an E rated tire is only rated to carry the same weight as the D rated tire. The majority of rims that come with D rated tires are only rated at 65psi, so plan on upgrading rims if you upgrade tires.

I went to 16" LT tires to get away from the 65mph limit and also gain some capacity. Not all trailers have clearance for larger tires however...II had to add a Correct Track Kit because it gave me the 2" of height that I needed to run LT tires.

With a 2011 mfg date, I wouldn't be too concerned at this point UNLESS you're planning an extended trip. Then, just for peace of mind, I'd replace. Usually around the 4 - 5 year time is when you need to start thinking tires - we're usually around the 4 year mark. Seems we always plan a trip about that time and rather than fret, we just bite the bullet.

Heavier duty tires are always nice... but to replace 3 year old tires in good shape? I would keep them. But...

If it is going to bug you the whole time you are towing, then replace them. Make sure you get a good trade-in for the relatively new tires, or better yet sell them yourself as some other lighter TT owner would probably love to have them.

The only issue I find is a load range "D" tire on an 8500lb dry TT! my trailer is 7100lbs dry and and I am running load range "E". your 8500lb dry is going to be at least 10k lbs ready to travel! I`de be more worried about the tires being being to small for the trailer (load rating).

I would replace them! I go about 5 years on a set of tires for the trailer. my Carlisles have at least 10k miles on them, with most of those in 90 degree temps!

I did not check the Carlisle, but E series, usually want 80 psi to get to 2830 load limit.
Many times the rims are only rated for 75 psi.
It is usually stamped on the rim somewhere, maybe inside the tire. Just a suggestion.

I found this when I went to E rated tires. Just my .02

EDIT:
I guess I should have finished Fast Eagles post. Sorry Fast Eagle!!!!

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