Tire upgrade

[MI.MARK]

We have an Elkridge 5th wheel. GVWR is 13500#. Original tires are Trail King 235/85r16e. Tire date is 10/17. After 3yrs. and about 15k mi. and one blowout it’s time to get new tires IMO.
I was leaning to Goodyear Endurance til I found out they aren’t available. According to my dealer they stopped production in the spring . Why? IDK. First thought was Sailun since I’ve only heard good things. Second, I’m thinking of going to 14 ply for load safety.
Any thoughts/opinions? Thanks

 

[steveblonde]

I put close to 35000 miles on my Trail Kings with no issues in 3 yrs finally they wore out. I check tires pressures alot ( from my motorcycle days ) i AM NOT a Goodyear fan (from my Toyota Supra and Corvette days)
Tire technology is always changing. I dont have any really good advise for you other than research. But 3 yr old tires are good in my book unless they are high miles.

 

[donn]

Your fiver was about the same weight as mine. I simply bought a set of BFGoodrich Commercial TAs. After a recall I replaced rhem with Michelins and never worries about it again. Any quality LT tire will do you far better than any crap ST tire made.

 

[Gary RV_Wizard]

Any quality LT tire will do you far better than any crap ST tire made.

Maybe, but you will need a larger or higher load rating LT because an ST of a given size will carry a lot more weight than an LT.

ST tires aren't inherently crappy (though there are some shoddy brands), but most have a top speed rating of 65 mph. Exceeding that can cause failures.

 

[Gary RV_Wizard]

I was leaning to Goodyear Endurance til I found out they aren’t available.

Have you checked other sources, e.g. Simple Tire, other dealer chains, etc? Some may have alternate warehouses or stock to draw from.

As for 14 ply, evaluate your axle load ratings vs the tire load capacity. Many trailers are factory equipped with barely adequate tire size/load ratings, but not all of them. If your existing tires have some margin in their carrying capacity vs "ust enough" for the axle GAWR, a higher load range doesn't buy you much.

 

[Rob&Deryl]

I put Goodyear Endurance tires on my trailer in July. The old ones were well worn and were 2017 according to the date code.

 

[donn]

Maybe, but you will need a larger or higher load rating LT because an ST of a given size will carry a lot more weight than an LT.

ST tires aren't inherently crappy (though there are some shoddy brands), but most have a top speed rating of 65 mph. Exceeding that can cause failures.

ST tires are rated at that false load at 65MPH whereas a decent brand LT tire gets its load rating at a much higher speed.
Now, lets look at common sense. The OP says his fiver weighs 13,500 pounds likely indicating he has 6000 or 6500 pound axles under it. If thats the case then a LT tire with a 80MPH 3042 load rating should be more than sufficient for his trailer.

 

[Gary RV_Wizard]

Yep, an LT235/85R16 can usually handle a 6000 lb axle at its max capability of 3040 lbs. But a Sailun ST235/85R16 would be something like 4400 lbs/tire and give him more than barely enough load carrying capacity. But at the cost of greater highway speed capability.

 

[donn]

By over tireing a trailer the resulting harsh ride can do untold damage. Thise Sailuns your citing are rated at what? 110PSI. The OPs wheels are not likely rated that high. So derating that Sailun to 80PSI its load rating drops accordingly.

 

[richclover]

The last set of Goodyear Endurance tires, load range E 80 psi, were speed rated to 87 mph. I’ll buy more if I can get them.

 

[Rich1961]

MI.MARK,​

What axles does your trailer have? Sounds like 6000 lb axles. If so, the Michelin XPS Rib or the BFG Commercial TA's have enough capacity for your axles, and are a great choice for replacement. If you have the 7k axles then a good choice is the Sailun. I had the Sailuns on my Arctic Fox and they worked well. Didn't need to run them at 110 psi as the axle weight was not high enough to need it. If you do go with a tire that is rated to 110 psi, make sure the wheels are rated for that high of air pressure. When the Westlake tires need replacing on our Cedar Creek, I'll likely go with the Sailuns again. FYI, the Sailuns are rated to 75 mph which is faster than I ever tow.

 

[Gary RV_Wizard]

By over tireing a trailer the resulting harsh ride can do untold damage. Thise Sailuns your citing are rated at what? 110PSI. The OPs wheels are not likely rated that high. So derating that Sailun to 80PSI its load rating drops accordingly.

Right, he would run the higher capacity tire at a psi suitable for his axle rating and actual weight, so probably 60-75 psi. The point is that the tire is comfortably within it's operating range rather than right at the max edge, which appears to be what Mi.Mark is looking for.

 

[MI.MARK]

Right, he would run the higher capacity tire at a psi suitable for his axle rating and actual weight, so probably 60-75 psi. The point is that the tire is comfortably within it's operating range rather than right at the max edge, which appears to be what Mi.Mark is looking for.

Gary
It has been my assumption that running lower air pressure was a recipe for disaster from heat buildup due to flex in the sidewall.
also by lowering the pressure am I not lowering the carrying capacity and therefore still running on the edge?

 

[Gary RV_Wizard]

You are conflating lowering the pressure below what is adequate for the load vs less than sidewall max load pressure. Different things. You want to always have sufficient pressure in the tire to carry the actual load - that's for both safety reasons and to maximize tire life. However, that pressure can be less than the sidewall value and that is not an issue. There is also a minimum inflation shown in the tire inflation tables - must stay above that to prevent excessive flexing. The tire engineers figure all that out when they create the inflation tables, so don't second-guess them. If their table says 75 psi will safely carry a load of xxxx lbs, they have taken all the factors into account. Conservatively so.

Under Tire & Rubber Assc standards, most 235/85R16 tires follow the same inflation table and it provides for 3060 lb of load at 60 psi, 3200 @65 psi, 3360 @ 70 psi, and 3480 @ 75 psi. You could safely run at any of those pressures. The tire has sufficient internal strength to handle much more, so it is not being stressed at all as long as the psi matches the load.

An anlogy: Consider a man who can bench-press a 200 lb weight. If you ask him to carry that 200 lb weight out to a truck, he can probably do it. But ask him to carry it all day long wherever he goes and he tires out quickly. Maybe falls and hurts himself trying to step over a small obstacle. But give him a 150 lb weight and he can go longer and farther. Not a perfect comparison, of course, but you get the idea. Performing at your max limit 100% of the time is always more taxing.