Toyota Repair: Sound when straightening out after turn, power steering rack, steering knuckle

Question
During the first 10 minutes, or so, of driving our 2000 Sienna Van, when I begin straighening out the wheels from a sharp turn, there's about a one or two second grinding/rattling sound that then goes away once the wheels are straight. It seems to go away after 10 minutes or so and the sound wouldn't reproduce at all after driving and hour to a Toyota dealer and driving with a mechanic in the van. It's definitely coming from the front end and was, previously, more noticeable during a sharp right turn, but now is noticeable when turning either direction. We recently had a new boot put on the outer joint on the driver's side, but this doesn't sound like a worn CV joint sound and doesn't reproduce when driving backwards in a parking lot slalom (a test I've heard that should accentuate a CV problem).

Answer
The noise may be coming form the tie-rod ends coming out of either side of the power steering rack, the only way to check them is to disconnect them from the steering knuckle and move them to see if the are binding up, another possibility may be a strut that is binding when turning, other than that I cant think of anything.