Left Rear Rub on Left Turns

[4wheelcycle]

I just changed over from winter to summer wheels/tires on my 2008 135i and now I have a slight rub in my left rear wheel, brake or suspension when I make a left turn. It's a quiet rub - I only noticed it because the days are warming up and I sometimes drive with the windows down.

At first I thought it was the rubber on the rear tire smearing around the turns and perhaps I only noticed it on the left because that side is closer to my open window. However, today I took a neighborhood left turn a little faster and it sounded more like metal rubbing - perhaps something related to the disk or the suspension?

Could I have bent the light metal guard behind the disk brake so that it rubs somehow on left turns?

All ideas appreciated.

Next step is to raise the left rear end and spin the wheel to see if it is on straight!

[M3 Adjuster]

possibly a failing wheel bearing..?

i would get it up in the air and make a quick check... a stethoscope can help you diagnose wheel bearing issues.

[4wheelcycle]

Although it is now five years old, my 135i only has about 23,000 miles on it.

I don't want to "hope" I did something stupid when I changed the winter wheels, but I also don't want to think it could be a wheel bearing this soon.