When is the steering stiff? all the time? Is the Power steering system making any odd noises like whining or anything? How many miles are on the vehicle? I would find it extremely hard to believe that a dealer service department would let a car out of there hands after doing work on it to remedy something if the symptom was still there...If your unhappy personally I would bring it back to them...PS fluid full? Drive belt tensioned properly? How does the "rag/universal" joint look on the steering shaft?