Box truck has Michelin tires on front, either Goodrich or Goodyear on rear. All bought at the same time 7 years ago.
Only driven maybe 5,000 miles since then so all tire treads appear as new but front tires developing small cracks in sidewalls. Rear tires still appear as new. Presume this is partially due to front tires being exposed to more sunlight....but 7 years ? Doesn't seem like enough time for supposedly top quality tires to develop cracks regardless. So wondering if Michelin had a bad run or what ?
Most of my Michelins get those cracks. But that is tangential to the fact that they outlast and outperform any other tire I've had.
In other words, they get cracks but that seems to not hurt anything.
Yeah I'm not sure what to think on the danger aspect... some authorities say replace, some say don't worry about it. A cringer to replace tires that expensive with 95 percent tread.Originally Posted by GregSYMost of my Michelins get those cracks. But that is tangential to the fact that they outlast and outperform any other tire I've had.
In other words, they get cracks but that seems to not hurt anything.
Tires dont last forever.
Most manufacturers and several countries in Europe consider ten years the absolute maximum.
A lot of people say five years.
And I know that tire stores will return any tire when it reaches 2 years old, unsold, for full credit to many manufacturers.
At 7 years, you are doing good.
But eventually, even with full tread, they will harden up, and, quite possibly fail, while still 'looking' new.
All kinds of parts on cars wear out just sitting, so a 20 year old car with 5000 miles will still need a ton of stuff replaced, particularly rubber, and plastic parts.
Most of the time your front tires will wear out faster because they have to turn the vehicle and are subjected to side load.
The Michelins on my dualy are 8 years old and have those little cracks, that said they have almost 100,000 miles on them.........
We have very intense UV where I live. My Michelins have cracking, but I'm not too worried about them. I sold an airplane a few years back that had weather checking on the tires and they were only a year old. The buyer gave me a hard time about it and I told him the truth--namely, the weather checking doesn't affect the strength of the casing and the air won't leak out--and that I wasn't going to do anything about it.
I had about 20,000 miles on my set of Michelins and still plenty of tread left. The sidewalls were looking pretty scary so I replaced them with some BF Goodrich tires (which I've had better luck with) a couple of weeks ago. It was worth the 'peace of mind'.
-Ron
Tires that sit seem to get more cracks.. It was explained to me that, as tires flex, oils and waxes come to the surface and protect against UV and ozone.. Tires that sit do not have the rubber flexed, so the surfaces are not protected as well.
Info from Bridgestone website seems to confirm that -Originally Posted by Davis In SCTires that sit seem to get more cracks.. It was explained to me that, as tires flex, oils and waxes come to the surface and protect against UV and ozone.. Tires that sit do not have the rubber flexed, so the surfaces are not protected as well.
Tires have waxes and oils specially formulated to protect against ozone damage built into their rubber compounds. When the tire rotates and flexes, these waxes and oils are forced to the tire's surface and are thus able to protect the tire. When a tire is stationary, these waxes and oils are not coming to the surface and thus the tire is at greater risk of ozone damage.
I had heard that tires must be run to prevent dry rot. That finally explains it.
I had to remove a set of 19.5' Michelins because of bad cracking, PA inspection laws required it. They were about 9 years old, with 60%+ tread left. 100K miles in 9 years, that's not exactly idle. $1000 of worthless tires. I won't be buying Michelins again unless it's for a vehicle that runs very high annual mileage.
On the other hand I have a set of Allstate (Sears) tires that were new in about '70 that are still fine, a pair of WWII vintage tires on another car that look like new. I even had an S-3 tire (WWII rubber rationing construction) that sat outside until the wheel rusted into oblivion that looked better than my Michelins. It's not the weather and it's not low usage that is responsible for my Michelins' cracking.
I read on a car forum that steel belted tires are recommended to be replaced at 6 years old because of potential rusting of the steel inside the tire. I understand there is legislation in the works to require it. Some speculate that the rubber is being formulated to go bad before the wire rusts so that the tires come off before they fail. I'm not a tinfoil hat guy but I wouldn't argue against that.
Originally Posted by MudI had to remove a set of 19.5' Michelins because of bad cracking, PA inspection laws required it. They were about 9 years old, with 60%+ tread left. 100K miles in 9 years, that's not exactly idle. $1000 of worthless tires. I won't be buying Michelins again unless it's for a vehicle that runs very high annual mileage.
On the other hand I have a set of Allstate (Sears) tires that were new in about '70 that are still fine, a pair of WWII vintage tires on another car that look like new. I even had an S-3 tire (WWII rubber rationing construction) that sat outside until the wheel rusted into oblivion that looked better than my Michelins. It's not the weather and it's not low usage that is responsible for my Michelins' cracking.
I read on a car forum that steel belted tires are recommended to be replaced at 6 years old because of potential rusting of the steel inside the tire. I understand there is legislation in the works to require it. Some speculate that the rubber is being formulated to go bad before the wire rusts so that the tires come off before they fail. I'm not a tinfoil hat guy but I wouldn't argue against that.
It's interesting that the WW2 tyres held up pretty well, I know of a guy who long ago was visiting a Royal Australian Navy warehouse where the staff carefully inventoried a pile of rotting disintegrating truck tyres from WW2, for trucks that no longer existed, because there was no procedure for disposal. Wasn't there rubber shortages at the time that required synthetic rubbers be used, maybe your WW2 tyre was synthetic rubber?.
My Toyota utility has Goodyear light truck tyres, I recently put the unused spare into use on the rear and noticed fine cracks on the sidewall that are not there on the tyres that had been used. So in my case, yeah, lack of use makes the rubber go off.
All the Michelins on our vehicles get the sidewall decay.
But we have usually been able to drive them to wear out before the sidewalls get scary-looking.
Speaking of scary-looking, about 20 years ago I built a small trailer to tow around the yard behind the Kubota.
My father-in-law gave me some wheels w/ mounted Goodyear tires that he had laying around since the 1960's.
They are hard as rock now, but still hold pressure w/ a tube inside!
I'm going to run them 20 or 30 more years, then that is it.
Frank
I've had the same cracking problem with older but otherwise 70% or so tread Michelin tires. One scary bit to add is that the rear tires on my BMW developed a crack following the flat ply all around the inside of the rear tires. They looked fine on the outside.
The car doesn't get driven all that much -- but it does get driven every week. In any case, pretty much impossible to see the crack all around unless you had the car on a lift or crawled under the car to look -- and the car still seemed to handle well. I was told the combination of the BMW rear suspension and Michelin tire cracking makes this a fairly common problem. The points here are that UV damage wasn't the problem (car is sheltered and the sun doesn't hit the inside of the tires) and it wasn't lack of 'exercising' the tire compounds (the car got driven regularly, just not a lot). It's the Michelin tire compounding -- and a suspension that wants them to sit flat.
Put new Michelins back on at a psi toward the high end (same as the old tires). The ride got a lot stiffer -- apparently having radial belts showing all the way through on the inside makes them a whole lot more compliant : - (.
I'm not likely to wear out the tread on the new Michelins at 3000 or so miles per year; but the overall performance still tests good enough to warrant their use on a per-year basis for another six or seven years. Or, so I hope.
How funny this thread came up today, as I was just reading about this in bed last night. It was in relation to RVs and tyres, as they tend to get used periodically. I don't know just how factual it is, as I'd never heard of it before, but the author claimed the cracks are due to oxidisation of the tyre compounds within the tyre casing. If the tyre is driven regularly the flexing causes these oxides to get 'pumped' out of the tyre and no harm is done. However if they sit there for long periods the oxides become trapped in the sidewall and begin to damage it. The solution, apparently, is to drive the vehicle for 20-50 km every few months.
As I mentioned, I have no idea if this is the correct explanation, however you'd think if it was was ozone damage it could be stopped with some after-market protector if driving the vehicle wasn't possible. It's not just car tyres BTW, not this is mentioned I've seen the same thing on a number of different tyres, especially older bicycle tyres that are unused.
Originally Posted by fish123. . .
Speaking of scary-looking . . . I'm going to run them 20 or 30 more years, then that is it.
Frank
Cut 'em up and sell them as urban alligator purses.
Just to add, I have Michelins on the front of my dually as well, same issue, I spotted the cracking about 2 years in (it sits about 95% of the time) and I was like what?? But as stated I wouldn't buy any other brand of tire. Until I have one unzip the sidewall I'm OK with the cracking.
Don't RVers put those cloth/canvass skirts over their tires to prevent premature UV rot when parking the vehicle for a long time?