2002 Grand Caravan sport steering problem

[mark with a van]

I bought my van used last summer and was happy as hell with it until I got the steering hose recall and took it in. After that it made a noise (mostly in the cold weather.) Took it back a couple times and was told that that's just how it is and my mechanic agreed. Most importantly, since then I have experienced it locking up when I try to turn right at start (ex. in a parking lot, pulling out of a parallel parking spot, turn right from a stop.) Only happens for an instant but for that instant it won't turn to the right.

The dealership that did the recall could find nothing wrong with it, so I took it to my mechanic. He also could find nothing wrong. He checked it all out and then I had it happen again. The next time he said he took it apart and made sure everything was greased up, the whole works. And I have recently had it happen again. I think I have a good mechanic as I've been going to him for 10+ years and have always been happy with his work.

Is there anything I can do with this other than trade it in and get rid of it? I know I'd take a beating in a trade ("do you have one just like this I could trade for? My wife doesn't like the color.") With only 53K miles I'd planned on having it a lot longer but I have small children and am worried about their safety.