Vibration above 60MPH, knocking when turning

[gamefreak]

When driving more than 60 mph down the highway I get heavy vibration especially from the back. Also when doing slow speed turns I get some knocking noise fron the front wheel, especially since the wheel bearing was tightened. I also get more play turning the wheel right than I do left.

Idler Arm was replaced (BTW how many Idler Arms are in these vans.)
lower ball joint replaced (Right Side)
wheel bearings retightened and greased up (Right Side)
tires balanced
shocks replaced

My rear brake shoes are going out so am having them replaced. Any idea on whats wrong, I'm leaning towards bad u joints. Any help would be appreicated.

[SilverBullet1997]

idler arms = 2, one each side up front.

I had a loud vibration noise with out any noticeable vibration, and a loud clunk when going to a stop and go. It turned out to be a completely gone bushing on my front u-joint, I had them both replaced.

[gamefreak]

Would a bad u joint also cause play in wheel.

[gamefreak]

Found out even at 200,000 miles that my U Joints where still good. However my driver side tie rod ends were bad. Also the problem with the rear end vibration was the wheel cover on one of that back wheels was throwing that tire into a slight imbalance. Had it taken off and van is now smooth even at 65 MPH.

Now to just replace driver tie-rod ends and get an alignment.