I put it in the A604 section because I thought it was coming from the shifter area originally, so I was thinking maybe something in the auto's shifter assembly could come loose and rattle. It might belong in general, I was just thinking "auto" when I was trying to figure it out. Sorry bout that.

It's not in any specific gear, just a specific RPM range. It's from 5k to about 6k, in all gears that I can reach that in.

I think I'm going to try to take the heat shielding off the cat, and see if that changes anything. From where I am sitting I know that the sound is coming from the shifter area, or under it if it's the cat. The sheilding doesn't feel loose, but I'll try taking messing around with it.

I was also thinking it might be a screw or bolt that came loose under the shifter, so I'll be taking that apart when it warms up.