Tie rod or Wheel bearing
 

How do you tell the difference in a bad wheel bearing versus a bad tie-rod? My 85 GSLSE front wheel when I jack it up, will wobble when I shake it from side to side as well as top and bottom.

Look behind the tire, at the tie rod. You will see if the slack is from the tie rod.
However, side to side play combined with up and down play, usually means wheel bearing. Tie rods will only cause side to side play.

I'll second that. If you have top to bottom play then you need bearings. Do yourself a favor and replace both sides bearings now. The other side will be almost as bad and will fail shortly anyway.

had same problem. wheel bearings

Mine had a similar problem. The tie rods were tight and the bearings were ok. It was the idler arm on the on the steering mechanism. Have some one take a look at it while you jockey the wheel around. If it moves, there is is your problem. Replaced mine (about $80 for the part) and all the wobble went away.

Have somebody crank the steering wheel back and forth while you look at the parts underneath. Also, hold the wheel (tire) at 3 oclock and 9 oclock and wrench it back and forth while feeling for movement (this will indicate tie rod end slop). Then do the same thing with the wheel off the ground and your hands at 6 and 12 oclock (this will indicate wheel bearing slop).

Idler arm can cause side to side play, but not up and down play, at the wheel/tire.

so basicly the same answer, if your wheel moves up and down, wheel bearing. its hard to tell without looking if it moves side to side as well.. because the bearing will move too. if your checking your tie rods its not as easy to diagnose without someone looking under the car when someone turns the steering wheel back and forth, as in put preasure on it not turn it the full range, so you can see the play on the joints.