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Old 12-03-2020, 08:36 PM   #21
Tireman9
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Originally Posted by ron3209 View Post
My Montana came with the ST235/80R16 China Bombs (max load rated at 3,420 per tire) made by Trailer King. After 6,664 miles I blew a tire on the driver side of the RV. Before I got to my final location to research and replace the complete set of tires, a week later I blew one on the passenger side after 7,188 miles. Thank the Lord that I had insurance to repair the $5,000 plus of damages to the RV. I did my research comparing the tires available to me and chose to replace all 4 tires with the Goodyear Endurance tire because they are now manufactured in the US with great QC. One thing I did to keep the E rated wheels, I upgraded the size to the ST255/85R16 that are rated at 4,080 lbs per tire. My GVWR is 16,715 lbs. If you consider the pin weight of 2,735 lbs, then the tires need to support 13,980 lbs. I increased the total tire rating from 13,680 lbs to 16,320. I now have 6,395 miles on my Endurance tires, which ride smoother, the handling is much improved and am more comfortable with the US tire on my Montana.

What was the cause of the tire failures? Were they belt separations or sidewall flex failure/ Didn't your tPMS give you timely warning? Do you have good pictures you can share?
I understand the GVWR. What is the measured actual load on each axle? The goal is to have the tire load capacity to be at least 115% of the measured load for the heaviest loaded tire. Need to assume an end to end load split for each axle to be at least 52/48 unbalance split and to use the heavy end for the calculations as very few RVs have an even 50/50 split based on some 20,000 actual scale weightings.
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Old 12-04-2020, 03:19 AM   #22
Happycamper2018
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i dont know your location but i only paid 133.00 a piece for my tires and 40.00 bucks to spin balance and mount , i think you can get them on amazon. i got mine from local garage, support small business.
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Old 12-04-2020, 02:43 PM   #23
ron3209
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I travel with a TPMS and it did not warn me of any problem. Why? Because it was a Blow Out. No loss of air before they blew. Literally, with both tires they went POW! Straight through the tread, not the sidewall. Then the sensor went off. No warning. Pics of both tires attached. Was it a steel belt failure? Don't know. By what I understand, Chinese manufacturers do not allow the moisture enough time to dry off, so moisture rusts the steel belt, which weakens the steel, which allows the air pressure to blow a hole in the tire. And all the other specs you asked about? That is why you have engineers to design and have the manufacturer put the correct equipment on their RV. The China Bombs barely meet the minimum specs. I don't know anyone who loads their RV and feels that it is necessary to go weigh their unit every time they move a box in their RV.
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Old 12-04-2020, 03:21 PM   #24
Tireman9
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Originally Posted by ron3209 View Post
I travel with a TPMS and it did not warn me of any problem. Why? Because it was a Blow Out. No loss of air before they blew. Literally, with both tires they went POW! Straight through the tread, not the sidewall. Then the sensor went off. No warning. Pics of both tires attached. Was it a steel belt failure? Don't know. By what I understand, Chinese manufacturers do not allow the moisture enough time to dry off, so moisture rusts the steel belt, which weakens the steel, which allows the air pressure to blow a hole in the tire. And all the other specs you asked about? That is why you have engineers to design and have the manufacturer put the correct equipment on their RV. The China Bombs barely meet the minimum specs. I don't know anyone who loads their RV and feels that it is necessary to go weigh their unit every time they move a box in their RV.

Based on the pictures i would classify both as 'Belt Separations" They might have been discovered before they came apart with a "Free Spin Inspection"

RE weights. You don't need to get on a scales every trip. Just get the real numbers once when the RV is loaded with the most "stuff" you expect to carry. This includes water, food, fuel tools, people etc. Just quoting the sticker max numbers is of little value given that the data from thousands of weighing shows that a majority or RVs have a tire or axle in overload when they are weighed at RV conventions. You would only need a re-weigh if you made a significant change in the RV as you should have a 15% margin. I got a "4 corner" weight early after making my purchase. I have a nice 20%^ to 23% load capacity margin. I do get on an axle truck scale once a year to make sure I don't have significant "weight creep" from all the little things I add as time goes on. Do you know what your actual weight margin is?

Don't know who is suggesting anything about moisture on the steel. It may be possible but how do some tires pass all the DOT tests when they would not know which tires are going to be tested. You don't "dry off" the steel belts as the brass plated steel is normally always kept in sealed, desiccated bags then in heated rooms before the rubber is applied, no water is used in tire manufacturing process other than cooling the extruded tread which doesn't get near the belts and is itself dry. This same process is used in every one of the dozen or so tire plants I have visited in N. Central and South America.
This idea of "wet" belts would be similar to claiming that cars rust out because Ford & Chevy rinse them off before painting.

Selection of tires is the RV company responsibility. Most select the lowest cost (smallest) tire that just meets the minimum requirements. Owners have, or should have, the opportunity to select alternate tires or maybe they should walk away from the sale.


BTW Where are th Big-O ST tires made? It says on the tire sidewall.
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Old 12-04-2020, 04:11 PM   #25
flybouy
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....Based on the pictures i would classify both as 'Belt Separations" They might have been discovered before they came apart with a "Free Spin Inspection" ....
I've seen you post this statement several times. I have a question from a strictly practical viewpoint. Unless you have a leveling system that's capable of raising the tires off the surface "free spinning a tire" can be a daunting task. So the question is, how often should that be done? Aside from the obvious answer of when you have another reason to jack up the wheel such as lubing bearings, adjusting brakes, etc.
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Old 12-04-2020, 05:18 PM   #26
Tireman9
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I've seen you post this statement several times. I have a question from a strictly practical viewpoint. Unless you have a leveling system that's capable of raising the tires off the surface "free spinning a tire" can be a daunting task. So the question is, how often should that be done? Aside from the obvious answer of when you have another reason to jack up the wheel such as lubing bearings, adjusting brakes, etc.

Not easy to give a specific answer an it depends on how many miles you travel. Also the ease or difficulty of getting a tire up in the air depends on your suspension design and what tools and equipment you have. Having said all that I would think once a year or once every 2.500 miles which ever comes first might be enough. This of course depends on how much of the tire load "capacity you are consuming.

Did you watch the video in my blog on how it was done and the results of the "Autopsy" of the tire? If you take your time you should be able to see radial and / or lateral runout.
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Old 12-04-2020, 07:56 PM   #27
flybouy
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Not easy to give a specific answer an it depends on how many miles you travel. Also the ease or difficulty of getting a tire up in the air depends on your suspension design and what tools and equipment you have. Having said all that I would think once a year or once every 2.500 miles which ever comes first might be enough. This of course depends on how much of the tire load "capacity you are consuming.

Did you watch the video in my blog on how it was done and the results of the "Autopsy" of the tire? If you take your time you should be able to see radial and / or lateral runout.
Haven't seen your video but I've seen runout from tire and wheel defects.
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