I was a Remington/Firestone/Goodyear/etc., tire dealer for years - I also trouble-shot for Triple-A on their vehicular fatalities, etc., and I can say that Michelins were responsible for more one-car accidents than any other radial tire. Period.
There's so much information to impart to you youngsters, but I will answer questions as they come to bear - and if something's not clear to you, let me know.
I left a lot of words out of the post here - and a lot of them have only 4 letters or less.... so they shouldn't be a problem ... but they made my answer a little
l-o-n-g.....
.... however ... I'll be here all week .....
Before this becomes TL-DR, I will ask if anyone has ever heard a vehicle going by with a LOT of tire noise? Do you know why SOME tires make so much noise - a rolling-rump-rump-rump type sound?
The biggest problems are:
A] tire rotation ... then
B] road damage ... and maybe
C] Bad tire technology/construction.
D] Wrong tires on vehicle - 40-inch MUD-N-SNOW PADDLEWHEEL tires on a K5 Blazer being driven on the freeway comes to mind.
Most tires don't like to be moved into a different position on a vehicle and have their job description changed from "power-acceleration/following" to "steering/braking/leading".
Even though I do not use Michelin tires for any of my vehicles, I still, never rotate any of my tires. I get excellent, even wear and reliability from tires that are watched closely and at the first sign of a possible bad wear pattern --- I REPAIR THE PROBLEM, and I don't rotate a tire to make it wear evenly in a different position.
►Once an oddball pattern is developed on a tire, it will continue building the bad pattern and may also pick up a new, secondary-bad pattern in a different position on your car.
►Once a tire is pattern ruined, it is by definition of the very word: ruined ... and moving it to a different position - no matter how well-thought out, etc, can cause carcass separations like you got.
Once a tire carcass separates, it is a hand grenade with a pulled pin.
Why do tires fail inside the carcass?
1. Striking a very hard object on the highway, breaking cords and corruption of its airtight integrity
2. Running at low air pressure or badly overloaded and run for a period of time.
3. Rotation to a new position causes cords to change position, cutting into each other and weakening the bond to the rubber and losing airtight integrity - causing a bubble and a potential blowout.
Most modern tires can
endure a Front-to-Rear rotation, but 5-point cross rotation is rife with problems.
It's a CORD-thing.
The cords are set into rubber to keep them in both a static and dynamic position and they are happy to perform that duty - and they have to play well with the other cords alongside ... and those crossing them ... (remember - these cords are in RADIAL tires and that's how the cords run - radially - or from the rim/bead on one side, to the rim/bead on the other side.)
Once a tire is rotated, the cords are subjected to different duties and they cut into other cords where they cross and run alongside. After all, the tire will have a few miles on it and the rubber is a living organism and it conforms to the cords
as they are when they were new.
But rotation creates physical problems to the cords as they have to play a whole different game with rubbing the cords in a different way and cutting across the others.
This weakens the cords though for a while they may not blow out or even bulge. Once they are run on a vehicle, then the dynamics of load/heat/pressure/directionality all change if they are put in a different work environment!
This is from where the bulges and bumps originate!
It's a madhouse lifestyle inside the cord layers - and rotating the tire to a different position makes the cords work under a lot of stress with which they are not prepared to comply.
The only caveat I can offer here is that with new rubber compounds, better cords and better knowledge of how things work inside tires, a front-to-rear rotation MIGHT be accomplishable without any dire consequences. maybe.
But never for Michelins! I don't even like their motorcycle tires.
Here's some tips I've gleaned over the years as a tire-seller and an anal-retentive user:
- At least once-a-month ---> look at and physically (with your flat hand) feel the tire tread. It should never have any sharp edges on it. (OK - 'never' is mebee a harsh word)
- Tires that have a sharp or feathered edge on the tread blocks, are out of alignment, underinflated or can be certain grades of manufacturer defective.
- Using a real digital pressure gauge, check the pressure in either A front or A rear tire to see what the pressure is like in a tire that has no tread wear or patterning problems.
- If you find a good wear pattern on (as an example here) A rear tire, then bring the other rear tire to the same pressure as the first one.
- Do this same thing to the front pair. Test a good looking/wearing tire against the other and even them out for pressure.
- In reality, most tires will require different pressures in front-to-back loading situations. (Check your door sticker)
About # 1 above --- if there is a buzzsaw type pattern ( ↓ ) on the tread blocks, then there are a few possible causes.
View attachment 854046
ONE is a rotational pattern that is actually a defect in the tire design.
Here's ↓ an example of hard braking or accelerating (this shows on 4WDs a lot).
View attachment 854054
Here's an exaggerated view ↓ of block feathering:
View attachment 854032
In REAL LIFE - tires are not perfect and there MAY be some fore-rear feathering to the tread blocks.
Some other scary tire pictures.......
View attachment 854048
THIS is an instant KILLER! ↑
This may ALSO be very thin brake friction material on the pads. It causes hot spots on the rotor(s) that you can feel in the steering wheel or your braking foot. If it gets bad enough, it will rattle the windows and shake the front end.
A perfect design will never have any sharp, hooked, feathered edges on them because they are all supposed to strike the roadway with even pressure and no untoward tread wear will happen.
View attachment 854050
This ↑ will be a fatality............
View attachment 854052
This ↑ is NOT photoshopped! I have personally seen this not just a few times!