My experience with pulley bearings is that when they go out they make a helleva lota noise.

When my air pump bearing went bad, it made a sound like a screaming chicken.

It was so bad that when I was driving through a supermarket parking lot, people walking by had to cover their ears.

Needless to say, I was very embarrassed.

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Paul S.

2001 E430, Bourdeaux Red, Oyster interior.
79,200 miles.

1973 280SE 4.5, 170,000 miles. 568 Signal Red, Black MB Tex. "The Red Baron".