2000 Ford Ranger Warped rotor?

I have a 2000 Ranger with a salvage title. I have fixed all the damage but there is still a brake issue. First, my ABS light is on, but the issue is that it seems as though the rotor is warped. As the rotor spins it makes a squeek at the same point on the rotor and as I push on the brake the squeek stops. I've replaced the rotor and the caliper and it still does it. when the pavement is wet or slick it actually locks up that wheel. Driving down the highway I can feel the friction. I'm getting frustrated with it. Any ideas? Is something else bent somewhere. It was in a roll over accident.