What causes this? I am sure that I did not hit a Pothole, the Tires only have 3000 miles on them.
Michelin Defender Problem
- Thread starter zmelli
- Start date
Warranty it. ASAP before it blows out or they try to deny coverage because you ignored it.
I already did, this tire was on the left rear, I also noticed the right rear was also starting to develop a bubble, I am going to warranty the Right one on Monday. I am just wondering how common this is. I have never had this problem with a set of tires before. The DOT's are 2022.
I may switch to another brand next time.
I found this on tire rack's website;
A strong bond between these various components is necessary to provide the desired durability. However the strength of the bond can be reduced if 1) any of the components are contaminated during manufacturing (resulting in incomplete bonding), or 2) components are damaged in service due to use while overloaded/underinflated, or by impact with potholes, curbs or other road hazards that pinch the tire between the rim and the road, or simply stretch the rubber beyond the elastic limit of the underlying cords and wires.
Past experience indicates that a sidewall separation/bubble caused by component contamination or incomplete bonding during manufacturing will appear within the first six months of service. Fortunately these separations/bubbles typically appear when they are small in size and before the tire's strength is substantially reduced. However since typical tires roll about 800 times every mile and the air pressure inside the tire is greater than outside, tire separations/bubbles that are unseen or ignored will continue to grow in size, further reduce strength, often generate noise and vibration, and ultimately lead to tire failure as the tire stretches under load (similar to the way that continuously bending a paperclip back and forth will cause it to weaken and break). However there is one last thing to remember; while a separation/bubble early in a tire's life is usually associated with a manufacturing condition, even a single, significant impact with a deep pothole or sharp curb can cause a new tire and wheel to be damaged.
A strong bond between these various components is necessary to provide the desired durability. However the strength of the bond can be reduced if 1) any of the components are contaminated during manufacturing (resulting in incomplete bonding), or 2) components are damaged in service due to use while overloaded/underinflated, or by impact with potholes, curbs or other road hazards that pinch the tire between the rim and the road, or simply stretch the rubber beyond the elastic limit of the underlying cords and wires.
Past experience indicates that a sidewall separation/bubble caused by component contamination or incomplete bonding during manufacturing will appear within the first six months of service. Fortunately these separations/bubbles typically appear when they are small in size and before the tire's strength is substantially reduced. However since typical tires roll about 800 times every mile and the air pressure inside the tire is greater than outside, tire separations/bubbles that are unseen or ignored will continue to grow in size, further reduce strength, often generate noise and vibration, and ultimately lead to tire failure as the tire stretches under load (similar to the way that continuously bending a paperclip back and forth will cause it to weaken and break). However there is one last thing to remember; while a separation/bubble early in a tire's life is usually associated with a manufacturing condition, even a single, significant impact with a deep pothole or sharp curb can cause a new tire and wheel to be damaged.
That's caused by either an impact which broke the ply cords or a slight gap in the ply cords during manufacturing. It might help if you called Michelin's 800 number and tell them about it and suggest they do something appropriate. Be sure to tell them there are no marks on either the tire or the wheel and you think it is a manufacturing defect! Mention BOTH tires! Do this BEFORE you go to the tire shop. It wouldn't hurt and it might help!
Some background: During the manufacturing process, components are applied in layers. One of those layers is a series of cords (like string) coated in rubber. These are the plies. In a radial tire, they are straight across the tire, 90° to the circumference.
A sheet of this material is wrapped around a cylindrical drum and cut where the sheet started. This area is called the splice. Most tire manufacturers use a bit of an overlap to prevent exactly what is pictured - a bulge. But some use a "butt splice" where there is zero overlap. Many tire building machines are automated, so the drum turns exactly the right amount to get the overlap desired.
At the end of the assembly line is a detector that measures the amount of sidewall variation. It is looking for both bulges and indentations (splice too large!) Usually this detector is mounted on the TUG (Tire Uniformity Grader) where the "out-of-round" is measured. The machine is supposed to reject bulges and indentations that are too large.
HOWEVER, some manufacturing plants use a quality system where instead of measuring every tire, a sample is taken and measured. If the sample consistently measures within a certain range, then the process is considered "Stable" and sampling continues.
But what if the range is too large? What's supposed to happen is that instead of sampling, 100% of the production is supposed to be measured until the process is again stable. Unfortunately, while the sidewall detector is relatively inexpensive, the TUG machine is not. The last time I checked (about 2005), a TUG cost $600,000 each, so many tire manufacturer may shortcut this step.
Some background: During the manufacturing process, components are applied in layers. One of those layers is a series of cords (like string) coated in rubber. These are the plies. In a radial tire, they are straight across the tire, 90° to the circumference.
A sheet of this material is wrapped around a cylindrical drum and cut where the sheet started. This area is called the splice. Most tire manufacturers use a bit of an overlap to prevent exactly what is pictured - a bulge. But some use a "butt splice" where there is zero overlap. Many tire building machines are automated, so the drum turns exactly the right amount to get the overlap desired.
At the end of the assembly line is a detector that measures the amount of sidewall variation. It is looking for both bulges and indentations (splice too large!) Usually this detector is mounted on the TUG (Tire Uniformity Grader) where the "out-of-round" is measured. The machine is supposed to reject bulges and indentations that are too large.
HOWEVER, some manufacturing plants use a quality system where instead of measuring every tire, a sample is taken and measured. If the sample consistently measures within a certain range, then the process is considered "Stable" and sampling continues.
But what if the range is too large? What's supposed to happen is that instead of sampling, 100% of the production is supposed to be measured until the process is again stable. Unfortunately, while the sidewall detector is relatively inexpensive, the TUG machine is not. The last time I checked (about 2005), a TUG cost $600,000 each, so many tire manufacturer may shortcut this step.
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I gave up on them decades ago for cord separation, and them copping out on the warranty. Now I'm glad I stuck with giving up on them. OP warranty them, that tire is not something I would want on my car in that condition.
Same here. I went round and round with Michelin a decade ago for the same issue. Initially denied then called Michelin and they agreed to replace the tire for “only” 100 dollars through DT . I agreed ( at least it was something) and haven’t bought a Michelin tire since!
My issues were long before that, and with more than one car over the years, shame on me. Some people hold Michelin tires in high regard, I will never use them again. As with everything Bitogo opinions vary.
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4WD
$50 site donor 2024
They certainly work for many - but between rock chipping and cracking - moved on as well …
Currently Cooper, Conti, BFG (mainly bcs of tread and C rated in 285/315)
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AZjeff
$50 Site Donor 2023
BFG was bought by Michelin a long time ago but the tires aren't clones are they?
BFG has far lower performance, especially in wet.
I have their Advantage T/A Sport on Pilot, and when wet, they are actually scary. From Tire Rack testing and other sites, their A/T tires are even worse.
As for the manufacturing process, they are made in Michelin factories.
They are not.
Allow me to expand further:
X-Ray won't show these bulges as the cord has a very similar density to the surrounding rubber. What X-ray is good at is finding air trapped within the tire, and how well the belts are placed. My guess is that some Michelin plants do sampling, not 100% x-ray.
Goodrich? There are a few exceptions but when Michelin bought Uniroyal-Goodrich, they got plants from both those companies - and it is common for tire manufacturers to do only a little upgrade over time as it is very costly to shut down production to replace major machinery. I am sure this is true for Goodrich tires. They are probably made in those old plants, albeit with upgrades along the line, but nothing like what a Michelin plant would have. Silk purse and all that! The way I think about Uniroyal and Goodrich brands is they are pretty close to what the rest of the industry does - that is, nothing special.
X-Ray won't show these bulges as the cord has a very similar density to the surrounding rubber. What X-ray is good at is finding air trapped within the tire, and how well the belts are placed. My guess is that some Michelin plants do sampling, not 100% x-ray.
Goodrich? There are a few exceptions but when Michelin bought Uniroyal-Goodrich, they got plants from both those companies - and it is common for tire manufacturers to do only a little upgrade over time as it is very costly to shut down production to replace major machinery. I am sure this is true for Goodrich tires. They are probably made in those old plants, albeit with upgrades along the line, but nothing like what a Michelin plant would have. Silk purse and all that! The way I think about Uniroyal and Goodrich brands is they are pretty close to what the rest of the industry does - that is, nothing special.
OEM or non-OEM tires?
Aftermarket.
What are your 3 favorite tire manufacturers regardless of price ?
I like reading your technical knowledge of the tire industry.
