Lifted my Disco with the Terrafirma 2" medium kit. While up, I noticed the tie rod ends were wore out so put in a Terrafirma heavy duty kit. Tighten everything up quite a bit, but it still seems to have a little wonder to it.

What else should I look at?

 

Alignment

 

Wander.
Yes as stated alignment
Or bad tires or ball joints or

 

maybe I should check the ball joints.

Alignment was done right after I did the lift and replace the tie rods. Right when I put on brand new BFGoodRich KO2 265/75 r16s.

What would I look for when I check the ball joints?

 

Excessive play in the joint

 

I kinda figured that. But how do I test for "play" in the joint?

Should I be able to shake it by hand? Do I have to take everything apart first?

 

Jack it up. Wiggle your tire up, down, in , out
You can use a little pry bar in there

 

Check your panhard rod bushings for play as well as the two bolts that secure the bar to the truck. I suggest replacing the panhard bar with an adjustable Terrafirma piece, I did I have been very pleased.
Your balljoints should be okay, from my experience they are pretty stout and don't fail on the regular.

 

It could also be your new tires. Give them some time to wear in. What pressures are you at?

I believe the consensus here says, 40psi f&r.

 

i know every set up differs, but i chalked out at 35/37 f/r