New(ish) transmission "rattle" (recorded sound)

[n2audio]

I have a high mileage Aviator, but the trans was rebuilt by Lincoln less than 2 years ago (26k).

There's a rattling noise that I originally feared was the motor, but it seems to be coming from the transmission.
It doesn't happen when the trans is cold, but shows up only after a couple minutes.
It happens at rpm changes - most easily from revving in park.
Also when accelerating from low speed. It isn't loud enough to hear on the highway.
Overall, it is still running and driving fine. Shifts are normal.

https://www.youtube.com/watch?v=h3u76kxCsVw

 

[n2audio]

Took it by a general mechanic today. Surprisingly, they traced it to the DS catalytic converter.

That's good news vs new trans or motor, but still not cheap.

I contacted a 2nd shop specializing in exhaust and they were somewhat cheaper -- still pretty pricey.


The cat system is generally sold in one large 3 piece assy. (Walker 16381 about $460 at RA). But I found one company (DAVICO) that sells it as individual pieces and the DS is right at $200. Warranty is the same as Walker.


Does anyone have any experience with Davico?