97 C1500 Sub. Front end/steering?

Hello All, I have a 97 C1500 suburban with 72,000 miles on it, I have this problem, when ever I make a right turn or go around a right curve, my steering wheel will let loose a little like someone grabbed it and pulled it to the right for a second or 2. Scary stuff when changing lanes at 70 mph. Just replaced the front shocks and had a real alighment done, but that didn't make it go away, any ideas before I head off to the chevy dealer to spend a fourtoune, would be greatly apprciated, Thanks.

http://www.automotiveforums.com/vbulletin/showthread.php?t=356676&highlight=EVO+Sensor

//2000CAYukon