Pete - you said the noise is between 55-70, is it an under accel noise or a noise when coasting? I have this noise at the same speeds when my foot is on the gas, if I take my foot off the gas, the whine goes away. Had it at the dealer 2 weeks ago, they SAID they drove another one and it did the same thing. 1) I doubt they had another to drive, 2) I doubt it made the same noise (if they drove another one), as mine only started this recently. Haven't had time to deal with it further yet, but it would help to know if your problem was similar. Most people that have complained of a rear end noise (or a whine) here have had the problem when coasting.
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