I am trying to help someone identify what the stamped codes mean on his 15x7 SSIII wheels (they have snap on center caps). They are on the inside part of the rim (only visible when the tire is dismounted).

The codes are:
DO 15x7 JJ 903
DO 15x7 JJ 975

From other Internet sites, it looks like JJ signifies use with disc brakes. 15x7 is obvious. Anyone know how to decode the DO and the numbers?

Thanks,

 

I don't really know about those codes, but on mine one was marked OD instead of DO. Plus there are date codes and a random B and D.

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