Joey, remember a CJ5 is short wheelbase with the "normal" Jeep shackle setup. It's reversed from most other vehicles. When you hit a bump, the force of hitting the bump is moved foward toward the object you hit. The spring flattens in response to the bump. It's anchored at the back, so the axle and wheel move foward toward the object. This is because as the spring flattens, the growth goes foward.
Now this ain't a bad idea at slow speeds. When you're trying to get traction enough to go up, around and over things off-road the extra force will help. However, on the highway it can be nerve racking.
There are two answers to the problem:
1. Live with it and learn the CJ handling characteristicts, or;
2. Do a shackle reversal, take a look here at M.O.R.E.'s site for a good kit, as well as a description of what a reversal does:
Without doing the shackle reversal, any bump, pothole, or rock in the road will be noticeable. The first time I took my CJ on the street, turned a corner and hit a pothole at 25mph I thought I was gonna die! The CJ seemed uncontrolable and prone to wander all over the street. It took a while to get used to how the CJ reacted to bumps and potholes.
Now if you're talking serious shaking, like a vibration in the wheels or steering when you're not hitting anything, now that's another matter. Give the Forum a little better description of the symptoms and the Formum readers can better address the problem.
Happy Holidays and Safe Jeepin'