Will driving 40mph and above I hear this noise coming from the rear, and when I start to slow down until I stop.

What is your question?

Roaring noise seem to be coming from the rear either the left or right while driving 40mph and more. Noise seem to disappear when I slow down until I stop.

What makes this problem better or worse?

It seems to disappear when I stop

How long has your 2010 Nissan Maxima had this problem?

2 to 3 weeks