I've seen similar issues discussed in long ago threads but with no resolutions. My 09 2.4 AWD Vibe with 60,000 miles is doing a strange thing where between 1500-2000 rpms at cruising speeds I hear anything from a rattle in the lower drivers side engine area kind of by under my feet, to an all out feeling like the floor of my car is going to fall off. It started off as an occasional tin can sound, but now has gotten worse.
Right now, I have it at my mechanic and he's stumped. He's checked the exhaust and catalytic converter and can't find where it's coming from. He's saying he may refer me to a transition specialist.
Just wondering if any else has had/solved this issue. Thanks!