Hello. I'm a new owner of a '90 240 wagon. Love the car -- has 187K miles, but was driven by the proverbial little old lady from Pasadena for the last 9 years, so it's in great shape.

I'm having kind of an odd problem -- in the morning, after it's been driven a couple of miles, I get an intermittent grinding sound from the rear. It doesn't happen every day and stops after a mile or so more. At first, I thought I ran over a branch or a cardboard box, but it's happened a few times now. Usually happens if the weather has been cool overnight (it does sit outside).

Any ideas what this could be? Thanks for your thoughts.