Funny noise on my L553 when i go around corners, left or right. Could it be a bearing?

[scottlandyard]

I had made a post about this a few weeks ago and got quite a bit of response. Thanks. I had a tractor mechanic listen to it and he said, don't worry about it. I cant do that. I'm wondering if the noise might be the chain binding on the sprocket when the front or rear wheels "steer" in corners? whats the tell tale sign that the bearings are bad? Also my brand new hydro 303 oil is cloudy. gray. Might this contribute to the noise? what would i be looking for through the access panels? Thanks in advance for your help.
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