Help Needed w/ a 128 Noise

[DocHam]

Okay, so, acquired a '13 128 today and discovered that it makes a scraping-type noise when accelerating quickly at higher speeds (@ ~70-80 mph it starts). I'll let off the gas and it stops after a moment, but the speed itself doesn't seem to be the cause. It seems like it's the act of accelerating.

This first minute of the video below is describing exactly what's going on, but the problem is the 128 doesn't use the identified part. It's too dark rn to go work on the car and I've had no success finding what part might be the 128's equivalent, so I'm hoping someone on here could point me in the right direction for when I start looking around tomorrow morning.