sometime when applying the brakes the pedal pulses really bad, other times it's as smooth as can be. when it shakes it's really shakes bad, like a bent rotor, but if one was bent why does it only do it sometimes? Any ideas??
Warped rotors. I had this happen in my 84 Daytona, it would just about shake apart when coming off the highway, but smooth at lower speeds. Changed pads and rotors and it's rock-steady under all conditions.
I agree, it probably is the rotors but a missing ABS tone ring tooth or a stripped and loose caliper hold down bolt could be other less common items. The stripped caliper bolt got me on the 1999 Dakota which used a similar setup to your 2001.