my tahoe rocks to the left and the right when going over some bumps. I have a 2001 tahoe that is lowered 2' in the front and the same in the back. The torsion bar was lowered without keys and I have bell tech drop springs in the rear. Is the rocking because of no torsion keys in the front, sway bar or shocks? I replaced the shocks with Bell-tech drop shocks about 2yrs ago