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Scary - AD07's about 1 year old cracking :(

Discussion in 'Roadster' started by wiztecy, Feb 15, 2015.

  1. wiztecy

    wiztecy Active Member

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    #1 wiztecy, Feb 15, 2015
    Last edited: Feb 15, 2015
    So cracking of rubber is bad, it means its too hard and won't hook up in the rain as spec'd. It also indicates its either old, been in the sun to long, or the compound is not right.

    After putting in my goretex patches on my headlights I took notice of cracks on my front AD07 tires and not happy. It hasn't been raining in Cali as much as it should, however to my own QA knowledge this is a FAIL and a safety concern to ALL who're running these! Please inspect your tires and ensure you don't have cracks! I'll email Doc@ the Tire Rack and let him know soon. High performance tires should NOT be cracking.


    IMG_7488.jpg IMG_7489.jpg
     
  2. supersnoop

    supersnoop Tesla Roadster #334

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    Where did you get these AD07's from? There were (at least) three different compounds produced, and some websites still stock the 2007 compound. If you bought old stock, that could be the problem.
     
  3. ecarfan

    ecarfan Well-Known Member

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    What is the DOT date on your tires that show cracks?
     
  4. jerry33

    jerry33 S85 - VIN:P05130 - 3/2/13

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    Were any products such as ArmourAll used on them?
     
  5. Doug_G

    Doug_G Lead Moderator

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    Those are just surface cracks - nothing dangerous - but it suggests that perhaps the rubber is old. Check the date code on the tires; even if you bought them recently they might be old stock.
     
  6. dhrivnak

    dhrivnak Active Member

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    Could it come from hard cornering? I have seen that after an auto cross.
     
  7. Doug_G

    Doug_G Lead Moderator

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    Driving the car hard you will get "feathering" on the surface of the tire. But this looks more like superficial cracking, suggesting that the rubber compound has dried out.
     
  8. jerry33

    jerry33 S85 - VIN:P05130 - 3/2/13

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    aka ozone cracking or age cracking. Generally cause by air pollution, chemicals, or being near an ozone source in an enclosed space.
     
  9. hcsharp

    hcsharp Active Member

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    wiztecy told me that the cracked tire had an invalid DOT code and that Tire Rack is looking into it. The code didn't have normal digits. It was just weird hash marks where the date code should have been.
     
  10. TEG

    TEG TMC Moderator

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    Maybe it was a tire intended to be sold outside of the USA (where DOT codes aren't required)?

    Also, this suggests maybe checking the other side:

    How old are your tires? | TireBuyer.com
     
  11. slcasner

    slcasner Member

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    Since the tires are unidirectional, then that means the tire on one side of the car would always be showing the incomplete DOT number.
     
  12. ecarfan

    ecarfan Well-Known Member

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    Yes, that is what I observe on my car with AD07's. Threw me at first when I was looking for the DOT code.
     

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