Okay, I did some searching on "howl" noises and didn't find anything definitive. My E has about 15K on it and was originally taken in for what I thought was bad rear brakes. I noticed a burning smell from the rear about a month ago. Dealer found nothing and said she was good to go. Burning smell persists and is accompanied by an intermittent "howl" as I drive along, usually at 50MPH and greater. The noise is also louder the faster I go and vice-versa. I can remove the "howl" by banking slightly to the left, but it usually comes back unless I jerk the wheel really hard. That tells me it may be a bad bearing? Along with this smell, which seems to be consolidated to the rear passenger wheel is a really warm/hot temp. to the wheel that is not present on the other side. I'm hoping whatever it is, the warranty will cover! Thoughts? 
