One problem related to steering gear box sector shaft has been reported for the 2005 GMC Sierra. The most recently reported issues are listed below.
: the contact stated the vehicle looses power steering at less than 5mph or while stopped and applying the brakes. The vehicle was taken to multiple dealerships at least six times. During those occasions, the dealerships replaced the gear box, shaft sector, power assist hose, pump and the pressure valve. The power steering problem still exist.