I did.. by accident...

Turns out (of all things!) none of the mechanics that have seen the car ever checked the muffler!

I was underneath the car trying to shake/move all kinds of suspension parts, when I raised my leg or knee and must have pushed against the muffler. It went CLANG as it hit the bottom of the trunk. The muffler mounts look fine but I can push it up about 1/2" and it will hit the car.

A 1/2" piece of wood wedged between the muffler and body seems to have TOTALLY fixed the problem!

Lesson learned... before people start assuming things and diagnosing other problems, check the simple stuff. I can't believe nobody ever grabbed the tailpipe and tried to move it. I was able to stand behind the car and reproduce the banging noise with my hand on the tailpipe just by lifting it. Didn't even have to get under the car!

The car is like new now. Of course I can hear small rattles and squeaks that I could never hear over the banging, and now THEY are driving me crazy. I need to look at the rear interior light and the sunshade for sure, because I know they're rattling.

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