Steering Troubles

Two weeks ago, while cruising down the highway, I got a horrible shudder from my front passenger tire (like a flat tire). I slowed down and checked for a flat, but everything was good (at first). A few miles later, same thing, only not as bad. I suspected a worn shock or steering component and got out and checked while my passenger turned the wheel from side to side while I checked for a worn component. I didn't see anything, so I kept driving, drove back home and drove all the next week. I kept an ear out for the problem the whole week and could notice something in the steering.
Then I decided to check under the car again, this time on a jack, and moving the wheel around by hand. I found the problem in one of the steering arms. After searching for parts online, and looking again to determine the exact part, I determined that I need a new center link tie-rod. The passenger side of this rod has about 1/2" of slack in it that moves when I turn the wheel. Something is obviously wrong with it.
I ordered a new part to fix this, but its going to be next Monday before it comes in. So, I've garaged it until I get the troublesome component fixed. I don't know how serious this is (I've been driving with it like this for awhile I'm sure), but I don't want a catastrophic failure when I'm cruising down I-20 in traffic.