Contain tire Blowout?

Every few months someone posts a question on one of the numerous RV Forums I monitor, asking if it is possible to prevent the damage done to the RV when a tire fails and has a belt separation or comes apart from a sidewall Run Low Flex failure.

 I have previously written on the idea of trying to "contain" tire failure on my blog but for those that missed the information here is a summary and links for more details.

In the tire industry, we have test drums surrounded by steel grating which weighs 6 to 10# per square foot so don't forget you would need a substantial structure to support a 200# - 500# "shield over each tire position. This extra weight would also significantly decrease the amount of "stuff" you can pack into your RV.
 IMO having worked around tire test labs, an effective "shield" on an RV is unlikely to work. I feel that prevention is a much better approach.

To better understand the problem I suggest you review the following.

1. Read this post.

2. This post shows the kind of forces we are talking about.

3. Check out the safety cage around this tire test machine.

4. Buy, program and test a TPMS

5. Every 2,000 miles or annually (whichever comes first) do a "Free Spin" inspection of trailer tires.


Prevention is much better than and less expensive than trying to protect your wheel wells.

Tire industry magazine announces expansion of SAILUN brand

Modern Tire Dealer, a trade publication posted this information on Sailun brand tires.

  I do know that there are many RVs running this brand in 16" and 22.5" sizes and thought this information might be of interest. 

Sailun Will Expand Passenger, Truck Tire Plants

Posted on March 11, 2020

Sailun Group Co. Ltd. has started major expansions at its production facilities located in Dongying and Shenyang, China.
“The project expansion will focus on plans to equip these additional production lines with the latest cutting-edge manufacturing and testing equipment, as well as increasing IT capabilities to meet domestic and global customer needs,” according to Sailun officials, who add that intelligent manufacturing and the application of big data will be the focus of the both expansions.
“Each facility will be equipped with the world's most advanced production equipment and fully automated tire logistics lines, aimed at effectively enhancing the level of automation, information, and intelligence of core equipment and enhanced AI in the tire manufacturing process.”
The Sailun Dongying plant expansion is a major strategic project for the Sailun Group.
After completion of the final stage, the factory expansion will allow Sailun to reach an annual production capacity of 27 million passenger tires.
The Sailun Shenyang plant expansion will focus on increasing radial commercial truck tire capacity and is also a strategic initiative for Sailun in 2020. Once complete, the plant will have an annual production capacity of more than five million truck tires.

Things to do while not traveling.

Ya it's really a pain to not be able to enjoy our RVs.

But There are a couple of "Projects" that may make life a bit better down the road.

Tire Inspection

Recording your DOT Serial

Testing your TPMS

Reading to increase your general tire knowledge.

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First is Tire Inspection. Here we are focusing on possible separations. This is a bit easier for Trailers but also it may be more important for them because of higher separation rate. First off you need to be safe. This means ensuring the trailer or Motorhome can not move. It may be best to hook up the trailer to the TV and set the brakes. Motorhomes can use the parking brake and put the unit in gear. For either type of RV you should block the tires that are on the ground so the unit does not move.  Not everyone will be able to do these steps, but if you can, here is what I suggest.
Jack up one end of one axle (motorhomes this means one end of the front) You then want to place a reference bar or pointer or stick near the tire, then rotate the tire watching the space between the reference pointer and the tire. Do this for the side of the tread and center of the tread. If you can see the relative movement of more than 1/4" you have a suspect tire. Mark the location where the tire is moving outward. you might snap a picture where you can also read the words on the sidewall at the location of interest for future reference. You might even consider a 10 second video that shows suspect movement.  I cover the general visual inspection and have a youtube VIDEO in THIS post.  I have a series of posts with more details on tire inspection HERE.
While Trailer owners can do this for each of their tires Motorhomes are probably limited to just "spinning" the front tire and even then need a HD jack.  Remember if unsure or do not have a solid surface to work on, or the proper tools, you may not want to do this rotating inspection.

If you have a suspect location you should contact your tire dealer. If you have a video you can show them that. Since they can see the tire close up if necessary they are in the best position to confirm there is a problem or to say all is OK.

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DOT serial. If you haven't recorded your full DOT serial numbers and kept that information with other important papers, this "downtime" might be a good opportunity when you have a nice weather day. Having this information might save you some time in the future if you hear there is a recall on your tire brand and size. Recalls are based on the DOT sericl and tires will be replaced for free if covered by a recall.

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Testing your TPMS.  I bet almost none of you have tested your TPMS. This should be done at least once a year. Some nice afternoon when you have nice weather with your traveling companion in the driver seat. AND when you have access to air of high enough pressure to top-off your tires. Go to each tire and unscrew the external sensor and have the person in the driver seat let you know that they can see and hear the warning for each tire position.  you don't even have to completely remove the sensor. Just unscrew enough to hear air leaking out. As soon as the monitor in the cab sounds you can screw the sensor back in to stop the air leak. Once you know that every sensor works you then need to go around and add back in the 5 psi or so that leaked out.
Doing this will also confirm you have your low pressure warning level set properly as the warning should go off as soon as you lose about 5 psi. I cover how I suggest you set your warning levels in THIS post.

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Finally, with all the time on your hands, you might consider simply reading through all the posts on my RVTireSafety blog. I don't expect you to remember everything but I believe that if you have reviewed the entire blog you will then know where you can go to get an answer to just about any question you might have on tires, tire pressure, valves, TPMS, weight and inflation.


Be sure to sign up for the weekly RV Travel Newsletter, published continuously every Saturday since 2001. NOTE By subscribing to RVTravel you will get info on the newest post on RV Tire Safety too
click here.

Side to Side Motorhome weight balance

Got this question and thought that others may have similar problem.

Hi I have followed your postings on this forum and I own 2017 Newmar Ventana 4002. I am trying to understand and resolve an issue with my coach where I have a 1000 lb difference in weight on the front axle side to side. I have had the coach weighed on all 4 corners 3 times and get the same results. My understanding and I think it may have been in one of your post that the difference should never been more than 500 lbs side to side.

I am having a conversation with Newmar about this and pushing them for answers why as I am well under the GAVR and well under the GVWR. I have unloaded and moved the contents in the basement and inside the coach around hoping to make a difference and the reality is I don't have much to move.

I am looking for any studies or evidence that I can show Newmar that this is not safe if indeed my information is correct that side to side should not be more than 500 lbs. I am hoping you might know of something I can get my hands on or someone I can talk to.

Thank you for taking the time to read this PM.

Sincerely,  Newmar owner.

My reply:

You may have misunderstood the side to side weight comments.

It is suggested that people get "4 corner" weights rather than just axle weights, as it is known that some coaches are unbalanced side to side.

We do this because if you only get axle weights and simply divide by 2 and assume your side to side weights are even, you could end up with an overloaded or underinflated tire IF the sides are not close to even.

Not sure where the 500# figure comes from other than looking at the load increments in the tables for each 5 psi. You will see that with some large tires the load capacity can increase by a few hundred pounds with an increase of 5 psi.

I do not remember ever seeing a "should" not be more than 500# different statement

You have confirmed that your coach is not balanced side to side and it appears you have made a good effort to get more balanced but have not been able to because of the design / layout of your coach.

With that in mind, and knowing the load on the "heavy end", you need to consult the Load/Inflation tables and use the heavy end weight to learn your MINIMUM inflation for all the tires on that axle. I still recommend you add 10% to the table inflation number as long as you do not exceed the max inflation rating for the wheels. This 10% helps avoid TPM low-pressure warnings due to an occasional drop in Ambient air temperature 

I trust you have confirmed with your RV Mfg that the wheels are capable of supporting the heavy end load.

I hope this clarifies what you need to do and answers the "Why" we suggest you get the weights on each end of each axle.

##RVT942