If you have a CJ that wanders all over the place and tries to kill you to death at anything over 40mph, check the ball joints. Not for free play or lift, but for tightness. Take the front wheels off, disconnect the track rod ends and see how easily you can swivel the hub. If you have to haul them round with both hands, there's your problem. You need a bit of resistance to prevent shmmy, but if there's too much, the steering can't self centre and you end up wandering all over the place. Have fixed mine and another one in the last couple of weeks by replacing the joints which had gone tight, and both Jeeps were transformed. Use Genuine Spicer joints if you can, I used Crown joints on one, and they're still tighter than they should be with the correct preload dialled in, although they did the job.
