2004 Durango. 4wd, 5.7 hemi with 210,000 miles. No ABS light. When braking at speeds above 40ish mph, there is a pulsing on the brake pedal (similar to, but not the same as emergency braking), and a shaking of the front end. You mostly feel it on the brake pedal, NOT in the steering wheel. As of January 2014 the front end has new pads, new calipers, and rotors (3rd set in 1.5 years). The rear brakes, I think the rotors were changed out just over a year ago (at least the pads were changed out).
We have been dealing with this issue for over 2 two years. I keep being told that the front rotors are warped, so I replace them without good results. Three different shops this week suggested I change out the hubs, also replace much of the rack and pinion. Their bottom line is, we'll keep changing things out until it is fixed.
What I suspect is that there is a communication issue between the front and rear ABS systems. Meaning: The front calipers were bad, the rears were old, the fronts have been replaced, the rears are jealous. I have a hard time accepting that the rack and pinion is the issue, there is no play in the steering wheel, nor do we "feel" anything wrong. There are no awful sounds coming from the hubs, and slip control and 4wd appear to be operational. However, there is about 3/16" play in the wheel from side to side (front end on jacks), but, there is no play when grabbing and pulling the tire top and bottom.
I tried to be as thorough as possible, if any one can direct me to a solution, I would be very much appreciated,
Ken

 

Sounds similar to what I had. I changed the rack and pinion and it went away. I had more of a clanking sound.