LT truck tires or 17.5 trailer tires?

Discussion in 'Tow Rigs and Trailers' started by jeepinmatt, Apr 15, 2020.

  1. jeepinmatt

    jeepinmatt Still Fat

    Joined:
    Mar 24, 2005
    Location:
    Stanley, NC
    Need some new tires for my trailer. I don't want to deal with blowouts. I'm of the opinion that LT truck tires are built better and more underrated compared to trailer tires. But in the 235/85R16 size I'd need, they are all rated at 3042lbs each. Load G 16" trailer tires are rated at 4080lbs each. 215/75R17.5 trailer tires are 4805lbs each.
    For simplicity's sake, let's assume the following:
    New LT tires, $600, 12k capacity
    New ST G tires, $500, 16k capacity
    New 17.5 tires, $950, 19k capacity

    I think the truck tires are way underrated relative to trailer tires. There's no way a decent quality load range E truck tire is more likely to fail than a $125 Chinese chunk of trailer rubber. My max load will be 3500lb trailer, 9000lb skid steer, 2500lbs of attachments. So 15k, minus 1500lbs of tongue weight, ends up around 3300lbs per tire on the trailer.

    So a couple of questions:
    How are trailer tires different from LT tires?
    How are the load ratings calculated for each (LT vs ST)?
    If LT tires are rated at 3042lbs at 106mph, what are they good for at 75mph speed index L like trailer tires?
     
  2. braxton357

    braxton357 Robot

    Joined:
    Apr 6, 2005
    Location:
    Morganton
    This would have been simple if you weren't a pos.

    Also, where are you getting 17.5 wheels and tires delivered for close to that price? Buy decent 16" trailer tires and make sure they aren't flat before driving off, you won't have a problem for a decade.
     
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  3. NCJeeplover

    NCJeeplover Well-Known Member

    Joined:
    Jul 25, 2009
    Location:
    Claremont, NC
    My next set of trailer tires will be 14 ply Greenball tires in 235/85r16. @mcutler can tell you all about it. He's been through it all.
     
  4. jeepinmatt

    jeepinmatt Still Fat

    Joined:
    Mar 24, 2005
    Location:
    Stanley, NC
    Let me start by saying :flipoff2:

    $100/wheel
    $123/tire 215s
    $10/ea for mount and balance.
    =$932
    Plus some tax and such. My friend Edward Bay has a website where he sells new and used items at auction or a discounted online price:
    www.eBay.com

    I wish it were that simple. I keep them inflated, and check before every trip. Current tires have a late 2014 date code, and I've killed 2 tires in the last 5 trips. Not hot, no sharp objects, no leakdown. Just boom. Hence the reason for replacing em all before I have to deal with that again.
     
    Last edited: Apr 15, 2020
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  5. mcutler

    mcutler Well-Known Member

    Joined:
    Apr 17, 2010
    Location:
    mt.airy nc
    Explained to me by my favorite big truck tire store; trailer tires designed for twisting better between axles than truck tires- truck tires aren't designed for those forces in they're construction.

    That said, 10 ply trailer are junk. I've been on 14 ply trailer tires, going on ten years. No more blowouts. Have even wore two sets out, with only hazard repairs. I've used 3 brands from Goodyear to Chinese. Same results. Chinese are $145 each last time I purchased (about the same as truck tires) , Goodyear were over $300. I think the only blow out I've had was to a serious chunk of metal in the road, but the blowout was much less violent than truck tire. Easier controlled in the mayhem.

    I thought like you for over 10 years and ran truck tires; couldn't get a year out of them with daily towing. Going on 2 years on the current greenball set.

    Sent from my SM-G892A using Tapatalk
     
  6. StretchASU

    StretchASU Well-Known Member

    Joined:
    Oct 17, 2006
    Location:
    Creedmoor, NC
    G Range 14ply 16's
     
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  7. shawn

    shawn running dog lackey of the oppressor class Administrator

    Joined:
    Mar 13, 2005
    Location:
    Raleigh, NC
    I'm still in the 14 ply 16" Sailun camp. I agree with Matt about the twisting forces on truck tires.
     
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  8. Croatan_Kid

    Croatan_Kid How's your hammer hangin'?

    Joined:
    Nov 4, 2007
    Location:
    New Bern
    The 16" Sailuns seem to have the highest load rating at 4400 lbs per tire. If I still had a trailer with 16s, that's what I'd have.

    With that being said, I absolutely love my 17.5s. Without them, I'd need a triple axle or tandem duals if I had 16s. I like the extra capacity cushion when fully loaded. Trailer and excavator are about 15.5k. I could get by with the 16" Sailuns, but figured I might as well go big and as far as I know, that's the only 16" tire with that load capacity. I could be wrong though. The chances of finding a matching one locally wasn't likely though.

    I liked that I got 8k axles vs 7k as well with the upgrade. I'm sure the differences are fairly minor...it just seemed like a good idea since I knew what I'd be using it to haul.

    FWIW, I've spun my trailer around fully loaded and the 17.5s just don't care. They roll a little and just skid across the pavement. I'm not sure if I'll ever wear them out or if they'll just dry rot from age before I've used them up.
     
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  9. shawn

    shawn running dog lackey of the oppressor class Administrator

    Joined:
    Mar 13, 2005
    Location:
    Raleigh, NC
    There's a set of bald 17.5s parked in front of my house right now, so it's possible... If difficult
     
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  10. benmack1

    benmack1 Well-Known Member

    Joined:
    Oct 13, 2010
    Location:
    Efland, NC
    Sailun S637 in 16”. Have them on my 5th wheel camper. No complaints or problems at 5 years. My unit is a 2016 big country 4010rd if you want to search what they are carrying around. Not tons of miles but holding up perfectly. I peruse the RV forums a lot and have never seen a failure reported for these. I’m sure there are some somewhere if you dig but point being they seems to hold up much the best in the ST class of 16” tire. I run with 100-105 psi just under the 110 rating. Anyway, my results for what it’s worth @jeepinmatt Good luck.
     
    Last edited: Apr 15, 2020
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  11. Croatan_Kid

    Croatan_Kid How's your hammer hangin'?

    Joined:
    Nov 4, 2007
    Location:
    New Bern
    I've got a goal then! I've put a lot more miles on it than I ever imagined I would.
     
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  12. rodney eppes

    rodney eppes Well-Known Member

    Joined:
    Feb 3, 2010
    Location:
    Mt.Holly NC 28120
    From what I've read, yes, the ST are built to Trailer towing standards, like twisting & ramming curbs. The set I run now are Maxxis, 205Rx15, g rated. I felt they were good enough for My towing needs, & lower priced than Sailun. RV & Horse folks seem to know the most on towing & ratings. I Did blow out a lot of tires on my first 2 sets. Cheaper ST rated C! But another comparison, the C rated was at 80% of load capacity, where the G, my load = 50%. I feel that makes a big difference too!
     
  13. skyhighZJ

    skyhighZJ Thanks for your taxes

    Joined:
    May 31, 2012
    Location:
    Aberdeen, NC.
    I have the Carlisle Trail HD on the cyclone 3950 and our 34’ stock trailer. They are all G load rating. A big thing for me is they are alway parked on concrete pavers and always covered with UV covers when they aren’t in use. I have had excellent results.
     
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  14. rodney eppes

    rodney eppes Well-Known Member

    Joined:
    Feb 3, 2010
    Location:
    Mt.Holly NC 28120
    I started with Carlisle, but were C. I also park on gavel & pavers. Sun doesn't shine on mine.
     
  15. jeepinmatt

    jeepinmatt Still Fat

    Joined:
    Mar 24, 2005
    Location:
    Stanley, NC
    How is a trailer tire designed to handle it better?
    What about the front wheels on a truck? What about tandem axle trucks?

    I'm not trying to be argumentative, I just want to understand it better. "Because it's for trailers" isn't academic enough for me.

    Every vehicle I have ever owned has had dozens if not hundreds of miles of the frontend sliding from enjoying the limit of traction on curvy back roads and interstate cloverleafs. Trucks, cars, Jeep, you name it. I've only had 1 blowout. It was one of the 35s on my Jeep when I crossed a set of railroad tracks (right beside @GONOVRITs day job as a matter of fact). Could have easily been something in the tracks, but I will never know. Yet I bet I've had in the neighborhood of 10 blowouts on trailers. I've put hundreds of thousands of miles on car/truck tires, but probably only 20-30k miles on trailers. That's 1 per half million miles on vehicles, and 1 every 2-3k miles on trailers. Do I just have bad luck? Maybe that's part of it, but I feel like there's more to it than that. Mainly I blame China. But I'm not sure how to best solve that, hence the reason for this thread.
     
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  16. shawn

    shawn running dog lackey of the oppressor class Administrator

    Joined:
    Mar 13, 2005
    Location:
    Raleigh, NC
    Beats the shit out of me. I thought for years that an all position tire should be a more durable, longer lasting trailer tire than a shitty ST tire that can't be used on a passenger carrying vehicle. But then you look at how much a LT tire rolls over when you turn a trailer, and how I couldn't keep the treads from coming off of them, and I started to think that maybe I was wrong about it.

    I'm no tire engineer, so who knows.
     
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  17. jeepinmatt

    jeepinmatt Still Fat

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    Stanley, NC
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  18. braxton357

    braxton357 Robot

    Joined:
    Apr 6, 2005
    Location:
    Morganton
    You think your poor tire luck might have more to do with always buying halfway ragged out trailers for a deal than it does ST tires sucking?


    Anyways, here's this:

    ST tire designation: ST stands for Special Trailer tire. ST tires are designed for use on trailer axle positions only. They are not designed for the load or traction requirements of a drive or steering axle. ST tires have strengthened sidewalls to prevent the tire from rolling under the rim in turns and when cornering. All ST tires have a maximum speed rating of 65 mph. ST tires feature materials and construction designed to meet the higher load requirements and demands trailer towing presents.

    Tim Fry, senior development engineer with Goodyear Tire & Rubber Company stated, “The major difference is reflected in the polyester cords used in ST tires. These cords are bigger than they would be for a comparable P or LT tire. Typically, the steel wire also has a larger diameter or greater tensile strength to meet the additional load requirements. Because of the heavier construction for an equal volume of air space, an ST tire is designated to carry more load than a P or LT tire.”

    LT tire designation: LT stands for Light Truck tire. One definition at www.tiresafety.com defines an LT tire as any tire line or size which would typically be applied on a light truck (SUV, pickup, van). As such it could be an LT-metric tire for use on a one-ton truck or a P-metric ‘light truck’ size of a typical tire used on an SUV. Light trucks (pickups) and SUVs differ from standard passenger cars in their overall strength, load carrying capacity, center of gravity, and driveline complexity. For this reason, the tire options for light trucks and SUVs are often more complex than passenger cars. Factors such as load range, ply rating and sizes vary greatly from those of passenger car applications.
     
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  19. jeepinmatt

    jeepinmatt Still Fat

    Joined:
    Mar 24, 2005
    Location:
    Stanley, NC
    To some extent, yes. But those excluded, I've had the same experience on other trailers through the years. The rate might improve to 1 blowout per 5k miles or something, but still approximately shitty.
     
  20. drkelly

    drkelly Dipstick who put two vehicles on jack stands

    Joined:
    Mar 21, 2005
    Location:
    Oak Ridge/Stokesdale, NC
    Maybe just tire age? How many years/months is the same set of tires on your vehicles compared to how long they are on a trailer?
     
  21. jeepinmatt

    jeepinmatt Still Fat

    Joined:
    Mar 24, 2005
    Location:
    Stanley, NC
    I definitely think that is a contributing factor. "Good" tires will have better rubber that isn't as deteriorated after 5 years. Whereas cheap tires have cheap rubber and will suffer greater deterioration over time. That's why I'm not trying to salvage the 2 remaining tires on my trailer, and am going to just go ahead and replace all 4 (probably the spare too). But I want to take this as an opportunity to spend smart money instead of just buying buying more crap. Also, don't want to throw away money on 17.5s when 16" LR Gs would get the job done, but I don't mind spending more if the value is there. Bottom line is I want to buy tires and be done with it for the next 5-10 years.
     
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  22. StretchASU

    StretchASU Well-Known Member

    Joined:
    Oct 17, 2006
    Location:
    Creedmoor, NC
    I just simply go by what I have replaced. I just replaced the ST tires on our enclosed due to rot and them leaking out the sidewall. Tread was still good. Being that they were ST tires, I know they were the factory ones and god knows how old the trailer is simply because my FIL never puts good tires back on any of his trailers. However, every single tire I have changed on my trailers and others that has delaminated for anything other than road hazards have been LT tires.
     
  23. NCJeeplover

    NCJeeplover Well-Known Member

    Joined:
    Jul 25, 2009
    Location:
    Claremont, NC
    I've considered going 19.5 on my trailer also. Mainly because that's the size tire my truck uses. I could get a set for the truck a little early and keep fresh rubber for the trailer. Here's some info on it...

    Why Choose 19.5" Tires For Your Trailer?
     
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  24. Croatan_Kid

    Croatan_Kid How's your hammer hangin'?

    Joined:
    Nov 4, 2007
    Location:
    New Bern
    I've got over 2 years on my trailer thus far. Never parked on concrete or anything and never covered. Any time it's loaded, it's almost to the trailer capacity. I just keep them up around 125 psi. It's been to middle Georgia, Northern DC, PA, all over NC, hopped curbs and stumps...you name it. Haven't even worried about the tires. It's probably about time to check the bearings and tighten them up though. I think I did rotate the tires once, I think.
     
  25. rodney eppes

    rodney eppes Well-Known Member

    Joined:
    Feb 3, 2010
    Location:
    Mt.Holly NC 28120
    I left home on a trip to Crossville Tenn. one time, & had a belt bust on the trailer near Shelby. I had a shitty spare of wrong size, & 1 good tire, unmounted. Put the spare on, & pulled in Walmart/Shelby. Simply asked them to install the good tire on the rim off the blown tire. First thing they said, Only if it's a ST tire! Surprised Me, but they said by law, they couldn't mount a passenger tire on a trailer. Glad at the moment I had a ST.
     

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