I know there are numorous threads about these but I've seriously done everything. balanced tires, aligned, new ball joints, hubs, trac bar, and trac bar mount. Dint have them for about a week, even drove from colorado to kansas without them, but one day I was driving down the road and I got them. Now I get them whenever I got over 50. what else am I supposed to do?

 

Steering.

 

Bent wheel or bad tire

 

my tie rod ends are tight and my tie rod is straight.

 

How are you checking to make sure your track bar and steering joints are tight?

Also, was the alignment done a full alignment including caster or just toe in toe out?

 

Bad tire possibly. Maybe one has a broken belt. Swap the rear tires to the front and see how it drives.

 

Cracked rail?

 

I have the same prob, haven't done anything about it yet except rotate the tires all that did was lower the tire notice a tad bit, I don't know how to check the other stuff...

 

Mine had DW when I first got it, had it aligned and it went away. Then after a hard wheelin hunting season it came back. Took a little figuring out, but turns out my frame cracked on the drivers side by the steering box. You could turn the steering wheel and watch the frame move an inch before the tires moved. and this is all with the frame plated on the outside with 3/16 and a front bumper with a 3/16 mounting plate that catches 5 bolts along the side of the frame! Time for a steering box brace and I plan to plate the inside and bottom of the "frame" as well.

 

there might be play in the steering box itself, I've seen those go to the dumps. otherwise my problem was my track bar bracket moving on the frame, so I got it welded up and now she's solid. no matter how tight I got the bolts it would still move like a half inch laterally. otherwise sounds like you've checked everything

 

You've not checked everything. You didn't mention caster angle (I know you said alignment but if they can't adjust your arms any further they usually don't even tell you), nor the condition of your control arm bushings.

 

have someone turn the steering wheel back-and-forth while you lay under the front end and watch everything move. pay close attention to the trac bar bushings. I had a BRAND NEW JKS trac bar that had WAY too much movement in the bushing at the frame end. I cut the bushing off and welded a flex joint on, and added a KOR hard bushing to the axle end. No more wobbles.

Heres the flex joint that I welded on:
http://www.summitmachine.com/index.p...tomParts&cp=fj

 

Castor, Control arm bushings and trackbar bushings have always been the first things I check.

 

Example of a bad control arm bushing...