>>damaging to the car to drive without power steering?
>I don't know but I have a related question:
>How often should one change the power steering fluid?
My Jaguar has a long-duration self-purging system...The old fluid is constantly purged at a rate such that the fluid turns over completely every 18 months.
The only hassle with this system is you have to manualy top up the fluid
once every couple of months and the old fluid ends up on the drive-way :-)