95 silverado, k2500, 8600 gvw. new ball joints, new tie rods, drive axles, front diff, shocks, hub assemblysand brakes. The truck has a 6" lift with 35's. aligned to -0.4 degrees on the caster, the rest of the truck is straight with that. It should drive straight. however it seems to jerk to the left or right at will in four wheel drive. Its better in four low.Like its grabbing a big rutt. Its nearly uncontrolable. Due to the weather I can't test if it does it in 2 wheel drive. any suggestions?