Circumferential cracks near wheel seating surface

[George Bynum]

Last time I pulled my tires to rotate them, I noticed cracks on 1 of the 4. This was the only one of the 4, inside only, probably 20,000 miles. Deepest crack is over 0.45" (11mm) deep; that's a dime in the crack. I had another set of tires on wheels and used them instead; this is certainly trash, but can anyone suggest what happened? From the markings (UPRW-138E, P-32660, K-11116), who made this tire and when?

 

[Eddie]

Too low tire pressure for the load causing excess flexing. Old rubber that has degenerated do to age and heat. Too wide a tire for the rim and this I have seen several times. Just a very low quality tire.

 

[Quattro Pete]

They look like puncture wounds rather than cracks.

 

[Kestas]

Can you read the date code on the tire? It's the last four digits after DOT...

Excellent pictures! You must do a lot of it at work.

 

[George Bynum]

Originally Posted By: Kestas
Can you read the date code on the tire? It's the last four digits after DOT...
There are 4 groups of 4 characters near it ... 227L DOT MDM3 29KR 2905. I think the 2905 is 29th week of 2005; I bought this in Feb of 2006 ... 7 months since manufacture? I've not noticed the cracks in previous rotations. The tire is still holding air despite the longest of these cracks nearly a half inch deep! SCARY.

Originally Posted By: Kestas
Excellent pictures! You must do a lot of it at work.

Thanks; these are the 1st tire pictures I've ever taken. I got a new camera (early) for fathers' day, did the pics then cropped them with MS PhotoEditor then reduced in jpg quality to get them reasonable for posting. Had full sunlight on the tire with camera (on tripod) and me in shade ... tripod, light and large f-number is the key, I think.

In response to another response suggesting size problems ... not likely; OEM fitment on OEM wheels, 215/70R15 on 6" wheels. On the low inflation ... these were on the used vehicle when I bought it, but dealer had done it, 4 matching; I _doubt_ underinflation unless in 1st 100? miles before I got it, and all cracks are on INSIDE of tire; outside looks perfect.

 

[CapriRacer]

George,

Find a tire dealer that handles that brand and see if they will do an adjustment. At best it will be pro rated based on the tread depth remaining. Given the age of the tires, and the fact that you aren't the original owner (the dealership was), they might not be willing to help you.

From the photo, this looks like it is a private brand tire, but the DOT number tells me it is made by Goodyear. That may be helpful if you can't located a retailer of the brand - you might be able to call Goodyear's 800 number and negotiate something.

From my experience these cracks are the result of some problem with the various rubber interfaces. For example, this crack could be where the white rubber and the black rubber come together (but the cracks are a bit too low for that) or the rim strip / sidewall junction (and normally these don't develop cracks) - and those are a few of the many tire related causes, and there are external cuases as has been mentioned - underinflation, rim width, etc.

These cracks are normally not a problem, as the cracks will grow until they reach the ply layer and then grow along the surface of the ply. Eventually, the rubber sidewall will fall off, leaving the plies and the structural stuff of the tire intact. But there are a few situations where the cause is not the rubber interfaces - it is a structural problem - and those can grow THRU the ples - very bad. How to tell the difference?

Structural cracks will be jagged and perhaps on a diagonal. Yours are smooth and circumferential.

 

[GMGuy]

Quote:
these were on the used vehicle when I bought it, but dealer had done it, 4 matching; I _doubt_ underinflation unless in 1st 100? miles before I got it


Considering they where already on a used car, there is a possibility they where driven severly underinflated by someone else.
Driving on a flat, obviously, will ruin the tire sidewall very quickly. Which you'll see when you dismount the tire.

Alex.

 

[George Bynum]

Originally Posted By: GMGuy
Quote:
these were on the used vehicle when I bought it, but dealer had done it, 4 matching; I _doubt_ underinflation unless in 1st 100? miles before I got it


Considering they where already on a used car, there is a possibility they where driven severely underinflated by someone else.
Driving on a flat, obviously, will ruin the tire sidewall very quickly. Which you'll see when you dismount the tire.

Alex.
All things are possible; that's the significance of the 100 miles; the dealer was a buddy of mine, and got the vehicle on trade with slick tires; he put these CHEAP round black things on it. There was less than 100 miles on the tires when I got it.

CapriRacer gave me the 3 answers I was seeking; internal bonding failure probably, unlikely to rupture before seeing worse damage, and the company making the private label things. Trying to get any warrantee is not worth it, even if I could; I like my tires to match as closely as practical. 2 of the 4 were down to tread where I'd replace them soon anyway. The question was academic.

 

[George Bynum]

Originally Posted By: CapriRacer
From my experience these cracks are the result of some problem with the various rubber interfaces. For example, this crack could be where the white rubber and the black rubber come together (but the cracks are a bit too low for that) or the rim strip / sidewall junction (and normally these don't develop cracks) - and those are a few of the many tire related causes ...
When I DO get new ones, I'll carry my tinsnips in with me and cut out this to look over and further satisfy my curiosity. There is a strip of white showing in (some/all?) of the cracks.

Originally Posted By: CapriRacer
These cracks are normally not a problem, as ...
I didn't have an accident bacause of them, and they are off the car ... thanks for your insight