Since I've been researching tires for our '14 5er, I have a couple ideas to throw out for knocking around here since the many folks on the two 'main' RV sites are too opinionated (read as hard headed).

I'm going to use LT tires and simply because I can't buy a kinda decent RV tire for less then ~$350/each that's made in a civilized part of the world. Brand hasn't been decided though the Bridgestone Duravis 500 and General Grabbers are near the top of my list as the Michelins would break the budget.

The Tow Max tires currently on the 5er are rated at 3640#/tire vs the 3042# for the usual LT's in that size. That gives me an OEM tire that's way overrated for the axles that Keystone in their rationale have used. Those axles are 5200# capacity and would have been a reason for rejection had I been observant. My error was that I counted lugs - it used to be that 6 would equal the 6K axles, 5, the 5200. Or so I had been lead to believe. This unit really needs 6000# rated. But I'll have to live with that now.

Using a 3042# LT tire will still stay well within each axle rating by 884 pounds - and in my estimation, well within any safety zone. There is no safety margin with an ST tire while the LT really isn't 3042, but 3169 considering the 120 Load index. Then there is the speed rating. The LTs are usually 'Q' at 99mph or 'R' at 106mph vs the ST's which are 65 regardless of make. I'll never drive anywhere near the LT speed ranges but extended driving time at 65mph on many interstates is ....... probably not going to happen.

OK, any flaws in my reasoning beyond the fact that many insist on ST tires which is their prerogative .

 

I think you are correct. I have always believed that the ST tires are just lesser tires than LTs. Theoretically, they are designed for relatively low rolling resistance as the tread designs need not be optimized for accelerative or steering traction. The problem with a good LT is in fact its traction; the scrub when turning should be greater with a better traction design, especially at low speeds. Now, that might contribute to more stress on the axle components from the increased side loading, but I wouldn't think it would be enough to cause a problem. Plus I refuse to put anything other than reputable, US/EU/Japanese-made tires on any of my vehicles. Good luck finding a ST tire made anywhere but China...

 

I seem to recall reading that LT tires have a stiffer sidewall compared to an ST and they may break down due to the sidewall deflection when making tight turns (like when backing). That said, there are lots of LT tires in use on travel trailers so I don't think it's gospel that LT tires are bad on a TT. I believe that ALL ST tires come from China. On the TT forums I read the Maxxis ST tire gets good reviews.
Our 5th has TowMax and I watch them closely and monitor pressure/temperature on the road with a tire monitor system. I'm also careful about my speed and always pull less than 65.

 

Lots of opinions here. Some info off the Discount Tire info page...

"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."

I believe the sidewalls are stiffer on an ST tire if remembering correctly.

 

I had to go the expensive route to get away from ST's and have enough capacity for the trailer.


To be fair I have personally never had a blowout on any trailer tire, ST or LT. More luck than anything.


But while I have heard and seen many a sad story with ST's, I have never heard anyone actually blowing an LT (other than G614's which are debatable as to whether they are ST's or LT's). But those were G's of around 2008. It seems they have made changes and they are again, trustworthy tires.


I can certainly see why you are miffed about 5200lb axles. That doesn't give you much wiggle room (checking against the GVWR of your trailer). But the LT's should give you enough capacity, as long as you stay on top of the air pressures.


Make sure the wheels are wide enough for the new tires and can handle any increase in pressure, and relax.

 

Stated on RVnet forum, some manufacturers are putting on LT tires from the factory.

 

I've finally decided on which LT tire I'm going to use on our trailer. It will be the Bridgestone Duravis R500RD. While Bridgestone wont specifically say that they are recommended for RV's, they do come darn close with this wording: " They can also be used for other vehicle applications in complete sets of four or axle pairs if available in an appropriate size, load range and speed rating to match the existing O.E. tires' performance category and specifications".

I will go on record and will say that if a reliable and domestically made ST with an appropriate speed capability of 75-80 mph were available, I would consider it. The $400 Goodyear G614Y would not work as my wheels aren't rated for 110psig

 

I have used LT tires on all the 5ver's I have owned. Current one had ST235/80/16's on it.....swapped out to LT245/75/16R Goodyear's. Were really close to the same size and everything has been fine!

 

I used General Grabber 245's on my last 5er. The only drawback is that they are up to an inch less in diameter which was fine on that one as a half inch lower was good but not necessary on the current one. As a side note, those Generals worked very nicely but I feel with a longer and a somewhat heavier trailer that the heavier Bridgestones will be a better choice

 

My 5er came with 235 80 16 Marathons. Max pressure for these tires is 65lbs. Second time out on the road, Had one blow out, and on another adventure had one where the sidewall split open all the way around the tire. It did not go flat but nevertheless had to be replaced. I changed to a 235 85 16 BF Goodrich Commercial LT tire (load range E) at 80 psi. These tires all but eliminated trailer sway, excessive bounce and have thousands of miles on them with no problem. I also put these tires in a major bind when backing into some of those tight spaces.

I also have a 14,000 lb. gooseneck that takes a beating. I found some load range G LT tires that are rated at 3900 lbs with 110lbs of air. They may be too heavy duty for an RV but they shure hold a load and hold the road without getting hot on the highway.

 

Marathons used to be a pretty good tire when they were made in the US or Canada and were supplied on our last 5er. Now that they are China made, they have gotten a poor reputation for near full load failure. The BFG Commercial TA's seem to have disappeared in 235/245-16 size in a standard tread - or at least I can't seem to find them locally or on Tire Rack or Discount Tire web sites. That would have been my first choice. If they 'reappear' in the next month, I'll reconsider. The 'G' rated tires seem to be either Goodyear, which are close to $400 each or Sailun. Unfortunately the wheels on our 5er will not support the 110psig fill pressure

 

Like an old lady - I changed my mind again
I cannot justify close to $200 more for the Bridgestones and ordered the General Grabbers. I got very good service from the Generals on the last 5er plus that 200 bucks would leave me enough left over for a big evening out with my wife at .... say ....McDonald's.

 

Had friend with a 5 er, went to discount and got the discovery (discoverer?) brand lt tires from them for it. They were a little bigger in diameter, cant remember if he also went to larger wheels. He has sold it and now has a Cl A MH. But he said he never had issues. I run Maxxis on my TT and they appear to be holding up well also.

The may have been geolanders as I think about it for the 5er. Again he got them at discount tire.

 

I ordered 10 tires from Cheap Tires Online | Find the Best Deals on Tires | SimpleTire.com tonight...
Got 6 Sailun S637 in 235/85R16 coming for the toy hauler and 4 Cooper tires for the wife's 2012 Focus...
Shipping was $193.xx and I got a 5% additional discount on the 4 tires for being a veteran.

I'll share pics when they come in...

 

Just got my new LTs installed today by a mobil installer at my home. The 48 pound General's are a whole lot heftier tire then the 37 pound China Bombs. I was surprised at how much weight was needed to balance them though - 3oz or so per tire.