I am pretty sure, but not positive that one or both of my ball joints are bad. I have a pretty significatnt shimmy starting at 60 and continuing on up through at least 80, haven't had it much faster than that.
When the front wheels are off the ground, I don't feel any movement when I pull on the wheels.
But when I was replacing my rotors and pads a few weeks ago, it seemed there was more play on the passenger side than the driver's side. A visual inspection didn't tell me anything, cause I don't know what I am looking for.
Before I pull the trigger on parts, I need to know the joints are bad.
I have done all the voo-doo to eliminate the shake. Wheels were balanced, air pressure is correct, and of course the lock nut is lined up with the valve stem.
Shaking in Texas.

 

If their is play in the front wheels chances are that a ball joint is bad. They aren't expensive so just relpace them if I were you. I have some sitting here waiting for me to put them in, but I can't do that till my wrist is better.

 

Actually, now that I think about it. I think your car has the ball joints in the control arms and you have to have the whole thing replaced or something. So, disregard my previous post. I dont' know what I'm talking about.

 

In regards to the cost, I highly recommend Sloan's kit. Search for "Sloan's kit" and i'm sure you'll come up with the necesary info. I used his kit and it was a great deal....$120 if I remember correctly and that is for both ball joints. You can do it yourself in a couple hours per side.

 

Or...because you have an '86, you can order the old style steel control arms w/ replaceable ball joints for $100 or less new and ball joints are $13/a piece after that. The only other parts you need is the old style sway bar mounts (you can get them from parts heaven or another dismantler) and you may want to replace your rear control arm mounts with the new bushing included, in which case you need the rear bushing clip which can be sourced from a dismantler (I had almost brand new M030 rear a-arm mounts so I used those instead). Thats what I did...

 

If you can get a wheel off the ground, get a pry bar, put it between the pinch bolt and the arm and pry upwards. If it moves, the bushing inside the arm is worn. There should be no movement. Obviously, the more movement, the worse the problem is. I'm currently working on an replacment set of bushings for the arms from OEM style material. Should be ready in a couple of weeks. Email me for further details.