AT LOW SPEED I WAS UNABLE TO STEER CLEAR OF AN OBSTACLE BECAUSE THE STEERING WHEEL BECAME VERY DIFFICULT TO TURN, ALMOST TO THE POINT OF LOCKING. I HAD TO FORCE THE STEERING WHEEL WITH BOTH HANDS TO HAVE IT MOVE AT ALL. THE LOCKUP CAUSED LOSS OF STEERING AND I STRUCK ANOTHER OBJECT. THE PROBLEM COMES AND GOES AND NOW IS BECOMING MORE AND MORE PREVALENT. DOESN'T SEEM TO BE ANY CONSISTENT PATTERN, HOT, COLD, SHORT DRIVE, LONG DRIVE, ETC. PROBLEM OCCURS WHILE TURNING IN BOTH THE LEFT AND RIGHT DIRECTION. AT TIMES I GET THE FEELING THAT IT HAPPENS WHILE APPLYING THE BRAKE. *TR