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EgorKC's avatar
EgorKC
Explorer
Jul 08, 2017

Worn out subject, wheels and tires

4 weeks ago had 2 year old Goodyear Marathon (bout 8M miles)blow at 67mph. $6300.00 in estimated damages. I decided to replace the factory aluminum wheels with steel since the rating of the factory aluminum wheel on it was a max rating of 3100 lbs. The wheel MFG recommended an operating load of 2500 lbs. Max GVR on our trailer is 12M so the wheel is overloaded even deducting for pin weight. The tires on those wheels always ran a bit hotter than I thought they should when properly inflated. Now have 3500 lb rated steel wheels and Sailun 14 ply (the Marathons we took off had 6ply sidewall stamped on them) 637's. Shop got mechanicals fixed before body work so we could take a preplanned vacation. Sailun's ran much cooler (3800 miles). The ride is obviously rougher due to the stiffer sidewall but that is expected. The Sailun's un-mounted were about 12 lbs heavier for same size tire.
  • Old-Biscuit's avatar
    Old-Biscuit
    Explorer III
    Jul 08, 2017
    2012 Wildcat........5 year old rig
    OEM tires were ???

    Replaced them at 3 yrs old.....2 yr old tires blew

    What pressure were you running them at....?

    The GY marathon 235/80/R16 E at 10 ply....3420# at 80 psi
    Where did you get 6 ply Marathons...and 65 psi??


    Sailun S637 235/80/16 G
    'G' rated (14 ply)
    4,080# at 110 psi

    If not using high enough rated rims and not going to use full capacity then WHY 'G' rated tires?



    2012 Wildcat
    11,875# GVWR
    1,715# DRY pin weight (based on UVW 9,855#-----17.5% very LOW pin weight percentage)
    Wet pin 2000# PLUS those 'E' rated tires would be sufficient capacity if run at 80 psi

    Think running them at 65 psi caused them to overheat ---heat KILLS
  • azdryheat's avatar
    azdryheat
    Explorer
    Jul 08, 2017
    I also don't get the OP's math. E rated tires are fine for his 5'r, he just needs a better made tire. Count me as one who never runs anything but a truck tire on any of my 5th wheels.
  • rhagfo's avatar
    rhagfo
    Explorer III
    Jul 08, 2017
    Your 5er is the correct size to run LT truck tires. 235/85-16 will have 3,042# of capacity, more than the total GVWR of your 5er. Running the "G" rated at the max 110# psi, will beat your 5er to death. Not only that if you are running a 110# psi then they are grossly over inflated, giving you far less braking traction.
    Sorry, I feel you over reacted to the blowout and put way too much tire on your 5er.
  • JIMNLIN's avatar
    JIMNLIN
    Explorer III
    Jul 08, 2017
    I've noticed lots of new folks with smaller trailers read our threads about going to say the load G Sailuns S637 on our heavy trailers. Then mistakenly think they would work great on their lighter weight trailer with 4500/5200/6000 lb axles and maybe 2600-2800 lb wheel loads.

    Tire experts tell us a 10-15 percent reserve capacity above OEM axle rating is all thats needed when replacing tires on a trailer.
  • EgorKC's avatar
    EgorKC
    Explorer
    Jul 08, 2017
    Old-Biscuit wrote:
    2012 Wildcat........5 year old rig
    OEM tires were ???

    Replaced them at 3 yrs old.....2 yr old tires blew

    What pressure were you running them at....?

    The GY marathon 235/80/R16 E at 10 ply....3420# at 80 psi
    Where did you get 6 ply Marathons...and 65 psi??




    These were 3rd set of tires. OEM were an off brand that I replaced after 1 year as they were not wearing well even tho I keep a compressor in trailer and keep tires between 75-80 psi (not sure how you determined I was running at 65 psi). I use a Tire Minder pressure sensor as well and check it regularly for PSI and heat. Second set Dealer put on Continentals. After a tire tread separation in year 2 I replaced with Marathons through the dealer that were recommended to me by a couple people 5th wheel with experience.

    I read the side of the Marathons 3 times and it listed the "sidewall" at 6 ply. I did not look father as I had already decided to replace wheels and tires.

    The "OEM wheels" had a part number and were stamped on the inside 3100lb. max. Research as I indicated in the OP showed a recommended load for those wheels at 2500lb. Thus I went with heavy duty steel wheels with a rating of 3500lb. This trip was to Monument Valley with daily temps from Kansas to Utah in the high 90's. The Sailun's ran cool the entire trip. I checked hub temps at every stop as well and those were cooler than I had experienced with either of the 3 previous sets. Aluminum wheels will gain more heat than steel and I suspect that could contribute to it.


  • Westcoasting's avatar
    Westcoasting
    Explorer
    Jul 08, 2017
    I have Sailuns on my work trailer and they are such overkill for a 5000lb trailer, but they are really good tires. Have gone through a few different ones in the last few years but went for these heavy duty tires a year ago and haven't even added air to them yet! Might be switching my travel trailer over to them when my current tires are done.
  • tinner12002's avatar
    tinner12002
    Explorer
    Jul 09, 2017
    JIMNLIN wrote:
    I've noticed lots of new folks with smaller trailers read our threads about going to say the load G Sailuns S637 on our heavy trailers. Then mistakenly think they would work great on their lighter weight trailer with 4500/5200/6000 lb axles and maybe 2600-2800 lb wheel loads.

    Tire experts tell us a 10-15 percent reserve capacity above OEM axle rating is all thats needed when replacing tires on a trailer.


    Some of that's incorrect as I don't believe you can use a G rated tire on those axles, at least on the 4500/5200 axles as they are 6 lug and you can't get a rim rated for enough pressure to run the G rated tires on those lug patterns.
  • JIMNLIN's avatar
    JIMNLIN
    Explorer III
    Jul 09, 2017
    tinner12002 wrote:
    JIMNLIN wrote:
    I've noticed lots of new folks with smaller trailers read our threads about going to say the load G Sailuns S637 on our heavy trailers. Then mistakenly think they would work great on their lighter weight trailer with 4500/5200/6000 lb axles and maybe 2600-2800 lb wheel loads.

    Tire experts tell us a 10-15 percent reserve capacity above OEM axle rating is all thats needed when replacing tires on a trailer.


    Some of that's incorrect as I don't believe you can use a G rated tire on those axles, at least on the 4500/5200 axles as they are 6 lug and you can't get a rim rated for enough pressure to run the G rated tires on those lug patterns.

    My '97 11200 lb 5er has 5200 lb axles and 6 lug Dexter axles/16" wheels. I have two other flatdeck ('08-'11 GN and bumper pull) with 6 lug 5200 lb axles/16" wheels which is a very common size ......regardless my point is folks think G tires work better on their small trailers. Such as a 4080-6006 lb rated tire on a trailer with 2500-2800 lb wheel load.

    And of course we often see where some rv owners mounted a tire with higher pressure than the wheel.

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