I dunno you might be having the same problem as Kevin to which no one on here has any answers to so far. I think it may be related to your issue with the front end popping. On Kevin's car we think the culprit is the spring seats both upper and lower causing the noises. We'll change 'em out, the popping and clunking goes away for a few miles, and returns not long after. See my post "For those with H&R and KYB AGX" for his symptoms and see if you're close.
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