2007 599 Exhaust Rattle

'07 599 GTB with 1500 Miles, has a low pitch exhaust rattle between 2800-3500RPM. the dealer "shimmed" a heat shield however, the rattle is coming back ( it diminished a little after the dealer serviced it, but has came back now). Has anybody had similar problems? Seems to be coming from under the passenger seat (or in the area). Can anyone provide a diagram or exploded view of the exhaust system so I can narrow it down? What are some things that could loosen and rattle underneath.


TIA.

 

Thanks,

looks like the rattle could be coming from in between the catalytic converters. Looks to be the only area that something could come loose in. Specifically near #24.

 

they think it's a oil pump now, I only got one reply. I'll take this part of the forum is slower. I'm a moderator on another forum, this one seems kind of dead.