WHILE DRIVING ON INTERSTATE 81 NEAR DIXIE CAVERNS, VIRGINIA, WHILE ENTERING CURVE ON INTERSTATE, THE STEERING SEEMED TO FAIL AND WOULD NOT TURN. IMPACTED THE GUARDRAIL AND CAME TO A STOP. NO OTHER VEHICLES WERE INVOLVED. THE SYSTEM TO ALERT 911 ALSO FAILED. THE HORN HONKED FOR APPROXIMATELY ONE MINUTE THE SIDE CURTAIN AIRBAGS DEPLOYED. TRUCK WAS DAMAGED ON THE ENTIRE PASSENGER SIDE. INQUIRED AT DEALERSHIP ABOUT STEERING PROBLEMS WITH FORDS AND WAS TOLD THERE WERE NONE. *TR