technical Diff

[hanneswilken]

Hi Guys,
E46 320d manual. Just for interest sake, on the back of the diff there is a small square aluminum bar ( 120mm x 25 square) mounted on rubbers- what is this and what is it's purpose.
This weekend it is me and a EGR valve, boost pipe and vacuum pipes inspection to get my fuel consumption better.
By the way original engine mounting for this car is R 3400 a piece

 

[Twinz]

I would assume the purpose of the bar is to absorb vibration and movement... But without seeing a pic i am just guessing.