Aww, just jack up the front end and start turning the wheels by hand. It could be wheel bearings as previously stated, but it could also be something silly like a separated brake pad or a hanging caliper. My guess is that if you poke around down there for a few minutes the problem will jump right out at you.

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-tp


1990 300SE "Corinne"- 145k daily driver - street modified differential - PARTING OUT OR SELLING SOON - PORTLAND OR. AREA - PM ME FOR DETAILS
1988 560SEL "Gunther"- 190K passes anything except a gas station
1997 S420 - 265k just bought it with a rebuilt trans. Lovely condition