i had my 99 boxster for 4 months now. i had similar problem (noise was loud enough to heard over the engine noise) and thought it was bearing issue since tires seem to look pretty new from the exterior. i brought it to the shop and they told me that bearing was good but rear tires worn unevenly for some reason. inside section of both rear tires were worn to the blocks and that was the noise i was hearing. i replaced both rears and no more noise.
i read somthing about axels being off which makes boxster tires wear out unevenly. am i expected to have another uneven tire issue even if i realign the car? (sorry to change the topic)
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