One problem related to electric power assist steering system has been reported for the 1997 GMC Yukon. The most recently reported issues are listed below.
Intermitten drop in steering to the right, mostly during corners. About a quarter turn of the steering wheel. Was told to me by a mechanic that gm has known about this and there is only one part from the dealer dealing with it. No aftermarket item. It was told to me that it is a speed sensor on the steering column that governs the speed sensor for the power steering. Durning a turn at almost any speed, the steering drops out a quarter of a turn. Quite a shock to someone doing 60 miles per hour on a busy freeway.