vibration, engine noise on 1999 Lexus SC400

Two problems: 1)Noticable vibration at 2000 rpm in Park. Noise heard about 65-70 mph like a harmonic sound (clothes washer sound). Tires have been replaced. 90K service performed in November including all belts, timing belt.

Asked by for the 1999 Lexus SC400
Possible Exhaust loose or exhaust manifold. good luck
Thanks for the quick reply. I will certainly follow through with this. I will let you know what I found out.