Morning,Will try to keep this as simple as possible. Doing the investigation of new tires. I was completely convinced to go with either Duravis or XPS LT tires . My rig GVWR is 12.7 loaded with 6k axles. So by the book I should be using ST tires which have a carrying capacity of 3500 each vs 3000 on LT.Several questions.If my rig has a GVWV of 12,700 why are there only 6k axles? Does keystone subtract the pin weight from what the tires/axles should carry?Would I be over stressing LT tires with the weight above?Also concerned with what I have read about 65 mph and overheating on ST'sI know all the discussion on LT vs ST, but the above questions are my main concern. As always I am probably over thinking this, but we still have 9 months to go and it occupies my time.. :-)

Your only real question is do you go with LT235/85R16E or LT245/75R16E. That question is usually answered by measuring the center to center distance of your axles. For the 235 you need at least 33" C to C. Pin weight is not included the the axle carrying capacity. Your tires will be carrying a little over 10K, and LT rated at 3042 pounds are a much better choice than cheap ST tires.I ran RIBs for 6.5 years and around 40K+ miles before selling them for 200 bucks on CL. I put R250's on this time base on about -50 bucks each. Our trailers are similar in size and weight. Both are good tires for a trailer. Do it and don't look back. Chris

12700# gross and you should have 15% of that weight on the pin I believe so 10800# are on four tires.3500x4=14000# Kinda appears that you have a margin of 2 tons with the ST's or would have TON WITH THE LT'S. If possible I would weigh each tire to get a more accurate idea of what you have. 65 mph? most people do not know that. You could read it on the side of the tire BUT? I, and most people I know do not drive faster than that. No bigge. I switched to LT's and I wonder the stress on the bearings when making sharp turns as the tires do not give like the old St's. When I replace these present tires I;m going back to ST's I know the ride got stiffer and can feel it in the wheel.

Your rig has 6K axles because they Mfg does not include the weight that will be on the pin or the landing gear.

The answer is LT tires only! No and No to ST tires of any type or size.

Nutinelse2do wrote:Morning,Will try to keep this as simple as possible. Doing the investigation of new tires. I was completely convinced to go with either Duravis or XPS LT tires . My rig GVWR is 12.7 loaded with 6k axles. So by the book I should be using ST tires which have a carrying capacity of 3500 each vs 3000 on LT.Several questions.If my rig has a GVWV of 12,700 why are there only 6k axles? Does keystone subtract the pin weight from what the tires/axles should carry?Would I be over stressing LT tires with the weight above?Also concerned with what I have read about 65 mph and overheating on ST'sI know all the discussion on LT vs ST, but the above questions are my main concern. As always I am probably over thinking this, but we still have 9 months to go and it occupies my time.. :-)I would rather run LT's closer to their Max load capacity, than ST tires with a larger margin. They cost more for a reason. Many will state ST are designed to take the sidewall stress of the tandem axle. Well commercial HDT run the same tires on all axles, drivers and trailers. There are no ST's in big trucks.

Can of Worms.. LT vs ST 13K trailer | Good Sam Community

Dennis_M_M
Explorer
May 19, 2014
Another vote for XPS Ribs
JIMNLIN
Explorer III
May 19, 2014
op asks wrote:
Several questions.

If my rig has a GVWV of 12,700 why are there only 6k axles?

Does keystone subtract the pin weight from what the tires/axles should carry?

You answered your question although its not just Keystone that does this. Using 20 percent of 12700 GVWR has a 2570 lb pin wight or 10160 lbs on two axles or 2540 lbs per tire. The LT E at 3042 times four gives your trailer over 12000 lbs of tire capacity for a nice reserve capacity.

Would I be over stressing LT tires with the weight above?

Absolutely not. We've used LT E at 3042 lbs capacity on 3/4 ton trucks 6000-6084 rear axles and 6k trailer axles for decades.

Using LT tires isn't a new thing out here in the real world of light trucking and trailers.
We used 14"/15" and 16" truck tires (LT) and P (passenger) tires for years before the tire industry gave us the infamous ST tire.
wandering1
Explorer
May 19, 2014
If my rig has a GVWV of 12,700 why are there only 6k axles?
Because that is all you need. Subtract the pin weight from the GVWR.

Would I be over stressing LT tires with the weight above?
It depends entirely on the weight capacity of the tire. Read the sidewall.

Also concerned with what I have read about 65 mph and overheating on ST's. ST or LT, do not run the tires faster than the max speed on the sidewall. Higher speeds than what the tire is rated for will cause the tire to overheat which will damage the tire.
NC_Hauler
Explorer
May 18, 2014
I will make it close to unanimous...go with the Michelin XPS Ribs....as also stated earlier, 15% to 20% of whatever your 5er weighs loaded is pin weight which is carried by your truck, not by your 5th wheels axle's or tires....
Splashers3
Explorer
May 18, 2014
I totally agree with BO Plenty....

XPX RIBS and sleep well at night!
rseymour21
Explorer
May 18, 2014
x how ever many that is for the LT
I increase my wheel size from 15" to 16" just so I could pick LT! I have not been sorry!
Allworth
Explorer II
May 18, 2014
Find some CAT scales and run it across hooked up to the truck. You will have a little over 10K on the axles. With a GVWR of 13,800 I have 10,540 loaded for extended travel.

LT

LT

LT

I like the B.F. Goodrich Commercial TA. Seems to be a good balance of price and wear. (LT245/75R16 LRE)
B_O__Plenty
Explorer II
May 18, 2014
Totally agree on using LT tires. My Ribs have been trouble free. There will NEVER be another ST tire on any rig of mine...I don't care what you ST lovers say. I've compared them side by side. ST is like a bicycle tire in comparison.

B.O.
FastEagle
Explorer
May 18, 2014
Nutinelse2do wrote:
Morning,

Will try to keep this as simple as possible.

Doing the investigation of new tires. I was completely convinced to go with either Duravis or XPS LT tires . My rig GVWR is 12.7 loaded with 6k axles. So by the book I should be using ST tires which have a carrying capacity of 3500 each vs 3000 on LT.

Several questions.

If my rig has a GVWV of 12,700 why are there only 6k axles?

Because the trailer's hitch weight is subtracted from the GVW and added to the tow vehicle.

Does keystone subtract the pin weight from what the tires/axles should carry? YES!

Would I be over stressing LT tires with the weight above? Probably not.

Also concerned with what I have read about 65 mph and overheating on ST's. I know all the discussion on LT vs ST, but the above questions are my main concern. As always I am probably over thinking this, but we still have 9 months to go and it occupies my time.. :-)

When replacing ST tires that are listed on your trailer's certification label you are going to have to take on the responsibility for the change. Unless, the vehicle manufacturer will recommend another tire design or a retailer will take on the responsibility for you and do so with the bill of sale. Industry standards will not support the use of replacement tires with less load capacity than the OE tires. Tire manufacturers are very reluctant to warranty replacement tires they consider a misapplication.

FastEagle
Me_Again
Explorer III
May 18, 2014
rhagfo wrote:
Many will state ST are designed to take the sidewall stress of the tandem axle.

ST tires are the dirty little secret of trailering. There is nothing much special about them other than they dodge normal tire industry standard with inflated rating based on speed restrictions and the fact that they kill few people. And they are cheap, really cheap to the trailer manufacturers!

They are highly marketed by an small number of manufactures and importers. And they were troublesome way before manufacturing was moved to china.

Those with 6K axles and under are lucky in that there are many LT tires available that will give much better service, with the two the OP noted being two of the best.

Install them, trailer on and don't look back. They will roll down the road easier and be more stable. The closed outer rib on the XPS Rib and R250 does not grub in tight maneuvers. Go look at the trailer tires at a truck stop and see what the tread pattern looks like. Hint, it will not look like the current ST tires, but will resemble the Rib, R250 and GY G614 trailer tire.

Chris

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Can of Worms.. LT vs ST 13K trailer

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