Ok, we finally figured out what the problem was: Cracked Motor Mount.
We've been trying to hunt down this noise.
At first my mechanic told me it was tire rub and cut away some of the inner wheel lining.
Rumbling was still there.
Car went back to the mechanic. I suggested RIGHT rear wheel bearing or loose motor mount.
Shop called back and said that they drove the car with a mechanic in the trunk, listening for the noise... noise came from LEFT rear and they thought I might be a bad wheel bearing. They weren't 100% sure but they would start with the rear LEFT wheel bearing.
This didn't make sense to me because the rumbling only showed up when turning LEFT (and under load). If anything I thought the RIGHT wheel bearing was bad.
Shop said that noise was loudest coming from the LEFT side when turning LEFT.
So we went ahead with replacing the rear LEFT wheel bearing. As they started to change the rear wheel bearing they noticed that the engine mount was cracked.
Cheers,
n.
_
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