WTF is this thing???

[RatLabGuy]

I took off my airbox and resonator to fish out a tiniy wrench I dropped into it (sick). That's another story.
For reference, '03 P5 manual tranny.
WTF is this thing? See link below... right in the center. It's a really dense rubber block of some kind bolted to the top left (as facing engine) of the upper transmission axial mount. Block is about 1" cube, fused to a metal plate and bolted to the mount. via a nice hefty 17mm nut.

http://www.rewazule.com/David/Mazda/WTF_Part/IMG_5100.jpg
(nice hi-res so you can zoom in)

It's just a solid piece of rubber, not connected to anything. Attached via an m12 stud, like it'd be heavy?

I don't get it. I can only imagine maybe in soem otehrm odel, some large component woudl connect there? Like maybe a side mount for an auto tranny, or component for a charger? But why even attach this useless block of rubber???

Some more pics of it removed, from other angles:
http://www.rewazule.com/David/Mazda/WTF_Part/IMG_5102.jpg
http://www.rewazule.com/David/Mazda/WTF_Part/IMG_5103.jpg

Sucker's heavy for it's size, a good pound or so.

 

[mspeedP5]

Harmonic damper to absorb vibration.

 

[dandan2]

looks like it was there to make ur ride more comfortable and quiet! pssssssshhhhh, who the hell needs peace and quiet! these cars already raddle like hell anyways! well mine does, with the awr motor mounts!

 

[maxchao]

So it's a harmonic damper...I was wondering about that too. I'm glad I put it back instead of take it off to save weight. How do they know by putting a heavy rubber there can rid some vib? Pretty impressive...

Josh