I have a Forester 2006 XS with a steering shuddering issue which my mechanics don't seem to be able to properly diagnose.
Here is the sequence of events:
Late 2013 - Whenever I would turn my steering wheel, while either stationary or moving slightly (i.e. taking off out of a car spot while at 45 or 90 degree turn - my steering wheel would shudder. This issue began subtly and became progressively worse.
NOTE: When the car was warm, the shudder wasn't as obvious. It seemed to only happen when the car was still cold.
I took it to my mechanic and they replaced the steering belts (2 of them) and the shuddering issue disappeared completely.
Roughly 4 months after the belts were replaced the shuddering returned again. It began subtly and became progressively worse.
I took it back to the mechanic, plus a couple of other mechanics - all of which were at a loss to diagnose the issue.
This is what they did do:
Checked the recently newly installed belts for wear and tension - all OK there.
They flushed out the steering system and increased the idle revs of the car - in hope that the problem would be less noticeable.
None of this has made a difference and in fact, it actually seems to have exacerbated the problem as it's now even worse than it was before I had the belts replaced.
NOTE: It's now happening also when the car is warm (not only cold).
Friends have suggested:
Belt is slipping
Issue with the power steering pump
Air in the system
Replacing the power steering pressure switch
Any ideas and advice would be appreciated.