RV Tire Safety – “China bomb” tires and McDonald’s fries? What?

24

By Roger Marble

I continue to see people talking about “China bomb” tires. As an engineer, this makes me a bit sad that so many people appear to have such a poor understanding of the difference between “causation” and “correlation.”

It is true that a majority of the tires on RV trailers that fail were made in Asia, and for many folks that means “China.”

But I would ask: If 90+% of the tires applied to RV trailers were made in “China,” why are you apparently surprised to learn that 90+% of the tires that fail in RV trailer use were made in “China”?

In an effort to make the difference between “causation” and “correlation” a bit easier to understand I have sometimes offered the following example.

If you check with people in prison you will probably find that 90+% have eaten McDonald’s fries. Therefore, it could be concluded that eating those fries can be considered something like a “gateway drug” to breaking the law and ending up in prison. I think we can see that that conclusion is not sound or reasonable, but clearly the numbers are similar to what we see in the RV community.

Yes, tires on RV trailers have a shorter life than in other applications, but the major reasons for the higher rate is clearly a combination of factors. Those factors include the documented very high percentage of RV trailers with tires in overload/under-inflation condition, as well as the clearly identified impact on belt separations due to Interply Shear due to the suspension design of multi-axle RV trailers.

 

Read more from Roger Marble on his blog at RVtiresafety.net.

 

 

Subscribe
Notify of

This site uses Akismet to reduce spam. Learn how your comment data is processed.

24 Comments
Newest
Oldest Most Voted
Inline Feedbacks
View all comments

Sally
6 months ago

Manufacturers moved to china because they have 0 regulations that are applicable to goods manufactured for the USA. It is on the honor code that any manufacturer make things that work correctly. It is not required. So, yes you can buy some things made in China that MAY work correctly. BY and Large the though the percentage is against quality if it was made in China. Typically whatever it is is made just well enough to last a few months, so you will be forced to buy it again.
A total PITA, and if you did this with tupperware and it fails you just throw it away. Low Risk of personal harm vs saving on the cheap. If you do this with Tires, your risk of personal harm due to failure increases significantly.
Risk Vs Benefit .
SO, is your Benefit of running cheaper tires worth the risk of damage, death or dismemberment that may result if it fails, even just once? That is the question.

That being said, our rig came with made in usa Carlyles(old and rotting as we drove it home) . Even as ragged as they were, the sidewalls were not bulging at full PSI. (Early 2015)
Within the first month we took the rig in to Discount Tire to get new ones as the belts were all visible on them. We told Discount tire we needed their best tire for Rv’s. They put on some ungodly China made tire, the sidewalls were bulging out and we had nothing in the rig. just dry weight. I could not beleive that was “the best trailer tire” they had. We never went back there.

So I proceeded to call every single maker of ST tire avail , or email to find out if any of thier ST tires were made in usa, if so where could i get their data sheet download.
Not one ST tire company I called or emailed had a ST tire made in USA. Sailun is a company we looked at However they only have 2 tire sizes and they are G rated tires, meaning they req 110 PSI to accomplish their load rating. What that means is for the majority of people with E rated tires wanting to upgrade they would need to have all new axels with new hubs installed just to run them. And that is a huge deal.

Fast forward to 2017 we kept looking. We hadnt taken our rig out yet because we were performing upgrades anyway. Goodyear released Made in USA ST Tires and have all the sizes you would be able to order from any China Bomb maker. We called 4 tire places in town, one local small buissness was able to special order them for us and put them on. DCT was not allowed to order them because they were not listed in “their catalog”, Nor Firestone, Nor the other shop. The small indepent could though and has gotten ALL our buisness ever since.
For our rig we moved from 235/80/16 china bomb 3042lbs per tire @ 80 PSI to Made In USA 235/85/16 GoodYear Endurance 3640lbs per tire @ 80 PSI.
We lost 10-15 PSI weekly in the China Bombs weekly. with no load Dry weight only. I filled them religiously. Even at no load and To tell you the truth I was concerned just pulling the rig up the road 7 miles to get the New Goodyear tires on because they made me so uneasy. I could not imagin what kind of anxiety I would have had relying on them to pull long trips.

Alot of Newer rigs are coming from the shop with underrated axels, or so I have read. Our Axels are Stamped. Made in USA by Dexter Axel(before they were bought by Lippert), rated at 6000lbs each, 12K overall, and we have a 13,500 GVWR, Our Dry weight is 10,200 we have an enormous CCC at 3300lbs. Our rig is 36.5 Ft with 4 slides. With our dry weight of 10,200, our axels rating 12K, our issue with tire buige WAS the tires. No Question.
SInce the switch to the Goodyear Endurance, I check often, however have only had to fill once in a while. When I do have to fill we are talking 3-8 PSI.

To each their own, risk vs benefit.

DW?ND
7 months ago

Sorry, I forgot to mention these tires are on a 34′ Class A motorhome – subject to heat, humidity and severe ND cold.

DW?ND
7 months ago

We have had 3 sets of Made in China tires. One set of Toro Tires and 2 sets of Dynamax Tires. The lst set of Dynamax went 10 years and about 15,000 mi.. There was no xthr checking or cracks and of course minimal wear. However, I keep them covered, except when rolling, and I check pressure before every movement – regardless of distance! I have also now purchased a TPMS and watch it religiously! I was apprehensive too when my tire dealer put on the lst set – but I have no complaints or undue concerns about mfgr process. Roger Marbles’ analysis with McDonald’s is right on!

Charles
8 months ago

Our coach came with so called “China Bombs” mounted on it. They were brand new according to the time/date stamp. It has been four years and 38k miles and they are wearing fine. I will add that I check and air the tires religiously prior to departure on each and every trip, long or short. I also don’t drive over 65 mph unless I am in a passing situation. Maybe I am on borrowed time with them but so far they are working out just fine.

Steve
1 year ago

Interesting discussion and I am sure you are getting tons of opinions like mine. What I will say is we have all seen rv’s driving with under-inflated tires or driving too fast. I believe this is a major factor in blowouts but we have no way of correlating this into the discussion. The mfg of the tire may or may not have contributed. However, I changes the tires on my 5th wheel to Sailun’s. The strength of the side-walls compared to the original “china bombs” is substantial. I drive at a reasonable speed, keep them correctly inflated, but I still like the idea of a stronger tire to load safety in my favor. I am not pushing a certain brand, but based on my research, I chose the brand I did.

Thomas Starling
1 year ago

Using compressed nitrogen instead of compressed air, available at a lot of larger tire dealers.
Nitrogen runs cooler, doesn’t increase pressure with heat near as much as AIR.
NASCAR and trucking industry has been using for years.

Roger Marble
1 year ago

Tire running heat is generated by the flexing of the rubber in a tire. The more flex the more heat. It could be argued that if the inflation pressure does not increase, as many proponents of using N2 claim then the tire will flex more which would actually result in the tire rubber running hotter.

Dry Creek
1 year ago

I have found the perfect balance. I like running an approximate 80/20 mix of Nitrogen/Oxygen. Sometimes I’ll let the O2 drift down to about 18% if I can find some quality Helium and Argon “spacer” gases. Every now and then some CO2 sneaks in, but I sternly warn it to stay out of my tires. Since it’s the heaviest component, I will roll my tires to where the valve stem is in the 6 o’clock position and “drain” the offending gas out…

Roger Marble
1 year ago
Reply to  Dry Creek

Wife & I got an absolutely GREAT laugh from your post. As a tire engineer, I can tell you that your plan is one of the best I have ever heard. Keep up the good work. Too bad more folks don’t “drain” the bad gas out of their tires.

Marmot
1 year ago

AIR is already 70% nitrogen. Thinking that a 30% increase in nitrogen will make any difference whatsoever is delusional.

Bob p
8 months ago

I don’t know what trucking companies you are referring to but I was an over the road truck driver and when I had a low tire I filled it with compressed air. In the company shops they also used shop air to fill tires.

Thomas Becher
1 year ago

Love your coulumn.Always interesting. That said, I blew 3 tires on interstate 10 in Texas on a 94 degree day. Brand new BLACK TOP ,80#’s in tires 4 years old Uniroyal made in the USA. Goes to show not everything made in the US is that good or made in China is that bad. I think the road was too hot?

Roger Marble
1 year ago
Reply to  Thomas Becher

Tom the hottest locating in a tire is at the belt edges, not the tread surface. This is even true at 200 mph at Indy. I didn’t know that Uniroyal made ST type tires or were they truck tires?

Lee Ensminger
1 year ago
Reply to  Roger Marble

I’d also be curious to know how FAST you were driving, Thomas. Could you share that as well?

Kevin Loving
1 year ago

Are you saying ALL tires are equal? Are you suggesting that there are not CHEEP TIRES that is used by the industry to save a buck?

Roger Marble
1 year ago
Reply to  Kevin Loving

Not at all. I am saying that there are a very small number of folks that have the knowledge and experience to properly diagnose tire failure and determine the “Root Cause” (i.e. do a proper autopsy). Simply claiming that a tire failed because it was made in a certain country is as scientific as claiming a tire failed because the plant building was painted blue. Take a look at the picture in this blog post http://www.rvtiresafety.net/2012/07/run-low-flex-failure-real-life.html
and without reading my analysis tell me why it failed.

Kevin Loving
1 year ago
Reply to  Roger Marble

I realize that quality is made in China. It depends on the specifications the item is made to. My complaint is that many manufacturers install tires that are not designed to carry the loads required by the RV they are putting them on. This decision to save money could literally be a LIFE AND DEATH decision! One of the reasons I bought a Outdoor RV is because of the tires that came on it.
I am not a “expert”, I HAVE to depend on people who are supposed to know what they are talking about.

Steve
1 year ago
Reply to  Roger Marble

I agree that just because a tire is made in a certain place doesn’t make it bad. But many of the brands are made in China and it is a true statement that the RV mfg’s. are putting on tires that have a history of failing. Some mfg’s. are starting to put a higher quality tire on the top models. Inflation, speed and AGE are factors in tire failures, but compare the material, construction and weight and some China tires are better quality and some will be “bombs”.

Roy Ellithorpe
6 months ago
Reply to  Kevin Loving

I would say that the RV industry would install the cheapest tire that they could buy – That MET the MINIMUM standard for the application. The user is responsible for correct alignment, and inflation.

John R McConnell
1 year ago

Roger what you say is true. Many tire failures are due to under inflation, overload or even tires that are too old. I have had issues with the China tires and I always check inflation each time I start a trip. I also use a temp gun to check temps of tires and wheel bearings. I had just bought a new toy hauler and we took a trip to Calif from Ala. We made it to Texas and had a blowout. I know the inflation was correct and the tires were less than two years old (date of manuf on tire) I replaced all tires with goodyear endurance tires. We have put 20k miles on those tires over two years and have not had any problems. The goodyears are rated at 75 psi for load and have a higher speed rating. It would be hard to convince me that china tires are worth the money.
thanks for your column, I read it each Sat.

Dry Creek
1 year ago

And the Goodyear Marathon ST rated tires were never thought of as being failure prone?

I know the inflation pressure of the tires on my RV are correct each day before I start driving. And, I know they are correct as I drive because I have a TPMS. You can’t assume that the anecdotal tire failure you cite wasn’t due to a slow leak that you weren’t aware of.

Jeff
1 year ago

ROGER: You forgot to mention that everyone in Prison is INNOCENT Too! LMAO!

Patrick Granahan
1 year ago
Reply to  Jeff

Enjoyed your most informative report….now I am considering giving up eating
McDonald’s French fries.

Bob p
6 months ago

I gave up on McDonald’s French fries when they changed their cooking oil, it changed the flavor of the fries.