Recently i have noticed that my power steering is extremely heavy and the steering wheel vibrates dramatically when reaching 70mph. I took it to my local garage, which a friend of the family owns and asked them to check it out. I checked my tyre pressures to ensure they were at the correct PSI and they balanced the wheels for me but this has not helped at all. Is there anything else i can check, fill up, drain out etc or has anyone else had this problem. Thanks :)