Raspy rattle under load.

[Velma_LGT]

I have a 2006 Legacy gt that has developed a weird sound.   When the car is under load around 2-3k it makes a metallic rattle, almost like a spitting sound, it's hard to describe.  Can't hear it unless the windows are down and I'm driving next to a wall or other cars. All the heat shields are tight and I don't see anything making contact where it shouldn't.  

It doesn't make the sound when revved in park/neutral or when it's torque stalled.  Car still seems to run and drive fine and makes plenty of boost.  I get no feedback knock or fine learned knock at all.   

All fluids are pristine and at their proper levels.  A used oil analysis was done 500 miles ago and came back perfect.  I was leaning towards a cracked header or up pipe but would think it would struggle to make boost.

I'm thinking about taking all the heat shields off for a more thorough inspection but the bolts are pretty seized up. 

Anyone have ideas or a direction to head in?   I'll try to get a video up asap. Any input will be greatly appreciated this noise is driving me crazy

  

[lmdew]

We bought an 06 Forester from a Subaru Mechanic which had a rattle.  He said it was internal to the muffler and a common fault.  I got a muffler out of the yard and it's been fine for the last 5 years.

www.car-part.com is a good source.  Get one from a location out of the rust belt!

[Velma_LGT]

Exhaust is aftermarket from turbo back, it seems like it's coming from the front passenger side of car.  This is the best video I could get on the way to work this morning.  You can start to hear it about 1/3 of the way into the clip. 

 

[Velma_LGT]

Still haven't been able to figure it out.   Doesn't seem to be getting worse.  A person on another forum suggested it might be a cracked flex plate or the torque converter starting to fail. 

[heartless]

flex plate is a maybe...

torque converter - probably not.. unless you are noticing shifting issues as well?

If it is shifting fine thru all gears, and downshifting when you step into it (like to pass, or getting on the freeway) then i sincerely doubt torque converter.

i would suggest getting a good mechanic to give it an inspection - they can probably pinpoint the issue for you... very hard to do without actually seeing the car, and hearing it in person (videos rarely offer the same sound quality as actually being there)