Why is the front end of my Jeep wobbly at about 35-40mph?

[Bruce]

I've got a 1998 jeep wrangler sport with a 4 inch lift and 33 inch tires. At appox 35-40mph the front starts to wobble...sometimes fiercely and I have to back down. I've had alignments done and rotated my tires thinking maybe that was it but still no joy. What could be the problem?

[DeezNutz]

Could be wheel weights (balancing), did they do that when they rotated them? Or maybe it is a wheel bearing, if the bearings or cv joints get too bad your wheel could pop right off. Go get it looked at before its too late.