I have a squeak coming from under the car, most prominently noticed at about 20-35 mph while steadily coasting. Only occurs at colder temps. (below 40F) and it goes away while driving in the rain. Dealer says it's the main center bearing. Lubrication resulted in a temporary fix...ie. until it rained again and washed things out (1 week later). Anyone else experienced this? Does it need replacing?