replaced everything....
everything is tight. inside of tires are bald ....
This is a more specific complaint. The causes are, either singly or in combination; toe-out, or excessive negative camber. The alignment settings of these two are to spec or not. If the vehicle ride height is set after the vehicle is aligned, it will throw the alignment values off.
When the vehicle is moving, the LCA will sweep back very slightly adding toe-out. It is caused largely by compression of the control rod and control arm bushings. The closer the alignment is to set 0ยบ, the more pronounced this will be.
The UCA is a little on the short side by design.* The problem with the short UCA is that when the suspension is in full extension, the UCA pulls the top of the tire in toward the center of the car. The LCA acts like a pivot and pushes the bottom of the tire out. This situation has the weight and traction of the car resting on the inside edge of the tire.
The difficulty created by this design situation is exacerbated in cornering. Body roll lifts the front tire on inside of turn causing the car to run on the inside edge of the tire tread and because of the turning of the vehicle, scrub the tread on the inside edge of the tire. Faster, tighter turns over rough textured roadways amplify tire wear. The effect is much like dragging one of those big old flat pink pencil erasers sideways across a rough surface. IMHO Installing front and rear anti-sway bars will help reduce the body roll situation, but will not eliminate it completely.
* The front end of the A-body, like most mass-produced cars, is a compromise. The designers were faced with two choices, either make the car wider for longer control arms, or make the engine bay narrower. All things considered, the choices made by Ma Mopar were pretty decent. The cars handle acceptably well and will accommodate nearly any motor that Mopar offered to the general public.
