Thanks so much for the responses, guys!
ants_oz : What you described is exactly my case. Not bad, not brutal, but it's just there. Hope you're correct.
4.8isX5 : About 140K on the clock, I'm sure my struts need replacement since they're original. But not that bad. I'll keep my eyes on it for the next few months. Thanks!
upallnight: It happens on high speed, because on low speed, when I tried to brake hard, it already stopped.

It usually happens when I get off the highway to a ramp, from ~70mph to 20~30ish in a short distance.
Ricky : WWII Bomber Drone, lol. I attached a picture here.

Could you elaborate more on the poorly bedded pads out of true rotors? Both thrust arm are original but the thrust bushings are all brand new. Thanks!
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01' 3.0i E53 (M54) with 164,000 miles

07' 3.0si E83 (N52) with 134,000 miles

08' 3.0si E70 (N52) with 91,000 miles