Last week I purchased a 169,000K 380 SEL in fine condition.But it has an excessive whining noise coming from what sounds like the rear of the car, audible at all speeds over 50kph on or off the gas. It does not sound like a differential noise and increases in volume with the cars speed.<br> I rang the previous owner and he said it was tyre noise from the 205 x 15' yokahamas. He said the car originally had 14' wheels and tyres, and the noise came after he fitted the oversize wheels and tyres. Should I believe him? what can I do to diagnose the noise other than change to original size wheels which I don't have?