My 2002 M3 is making a roaring sound in 6th gear only between 50 to 60 mph at accelleration. When I was at the dealer for inspection 2 I pointed that out and the tech and we test drove my car together so they knew what I was hearing. After all that they so this is normal. Does anyone else notice this or have a similar problem.

Describe "roaring" sound. You could be referring to a rasp/drone noise?

Correct me if this is not it at all.

50-60mph on 6th gear might be around 2200 rpm if I am not wrong and is lil bit bogging for the engine, probably thats the reason you get a weird sound. or maybe its the rasp/drone longms mentioned about.
I try to keep my rpm above 2700rpm always(gears 5th and 6th).

Yes it is around it is 2300rpm but as a test going 40 to 50 mph this roaring doesnt happen and thats at 2000rpm so I really dont think it is the engine bogging down because it is still pulling like it should.

p.s. To explain the noise it is like if transmission had a chain that was loose if that helps