Do these lower the car at all? Is first question,

2nd is this one of the bigger dips/bumps you have encountered?

Car loaded up or just you?

How many miles on this setup?


With those answered you'll be able to pinpoint it better... at this point i would say the fronts dont have bump stops installed and perhaps it bottomed out and thats why you heard the clunk vs just a bump hit but no noise.

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2006 X5 4.8is Fully Loaded