Where is this KNOCK coming from?

I have an 89 Olds Cutlass Supreme that is in fantasic shape. I make sure I maintain it the best that I can.
Anyways, last month it all-of-a-sudden started making a "knock, knock,
knock" sound sometimes when steering slowly. It makes no noise at all if going straight. Sometimes when turning quickly I will hear a quick "knock" or two but it's not as bad or noticable as it is when I am going slow.
Sometimes I can't get it to do it, but I've found out the easiest way to ALWAYS get the noise to happen. First, I park, stop, put the gear shift in Park, wait a minute, then put it in Reverse, back-up slowly with the steering wheel turned all the way to the left, once I am backed-up, put it in Drive, and turn the steering wheel all the way back to the right, then start to accelerate slowly.
If I do this, what will happen is that it will "knock" about three or four times while backing-up, and then again when I turn the opposite way and start to move forward. After this, it's pretty much completely random...sometimes it will make a quick single "knock" here or there and sometimes it will be completely silent. But if I always do the above parking and backing-up procedure, it will always do it.
When the "knock" happens, I can kind of FEEL it in the floorboard via my feet. I've been in the passenger side while my mechanic was driving and I could FEEL it in my feet on that side as well, even though it SOUNDS like it's coming from the drivers side wheel well.
Further more, I took the car to my mechanic of 3 years now and he found that my drivers side ball-joint was worn pretty good. The passenger side one was still in perfect, solid condition. It kind of surprised me because I replaced both ball joints 2.5 years ago and I thought they would last longer than that!? But I thought, "oh well, at least the knocking will be gone". I was wrong! It STILL knocks just like before with the new ball joint!:(
I took it back to him and he raised the car to look underneath. We both looked for about half an hour but couldn't find ANYTHING that would cause it. Everything was nice and 'tight'. Over the past 2 years I've replaced both wheel bearings(hubs), upper strut bearings, ball joints, and tie-rod ends.
My mechanic said he honestly doesn't know what the heck it is. He said it could be a worn U-Joint in the axle but said that is still a long possibility.
Last month I had both wheel bearings replaced with new ones. What I am trying to think is whether the noise started BEFORE, or AFTER they were replaced...if the noise started AFTER they were replaced, what could the place that installed them done to cause this sudden annoying noise?
Sorry for being so long but I wanted to give as much detail as possible!:)
THANKS!:)
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CV joint ? On 29 Apr 2004 06:26:39 -0700, snipped-for-privacy@yahoo.ca (bigbossfan80) wrote:

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