Interesting bulletin MBDOC. Our 96 has the same symptoms, I think it's the speedo on ours. I know the speedo on our cars is electronic (no speedo cable into the dash) but the noise is so speed dependent I think it MUST be the speedometer. It occurs at 30 - 55 MPH on ours, sounds like a buzzing plasticy vibration. I will take my stethoscope on the next drive to be sure.
RIP "Betsy" (Oo=*=oO)
'96 E 3 2 0 (W 2 1 0) M 1 0 4 (Totalled)
Spaces in sig so as not to screw up the SEARCH; every time someone searches for that MB they don't want my sig!
2004 Audi A8L
'98 VW Passat 1.8T 5M
'87 Alfa Romeo Milano 2.5L 5M
'67 Impala convertible, 327cid