I went out to the hangar today to pull some maintenance on the van. It had started to make strange sounds in the front suspension. I figured I would grease up the ball joints and see what happened. Easier said than done. I had to pull the front tires to get at the lower grease zerks. I found that I had to pump a LOT of grease into the joints. I don't know when they were greased the last time. I drove it around for a while afterwards and the noise seems to have vanished.