Had a similar problem on the Durango until recently.
Brake pulsation - more noticeable at lower speeds obviously - even though I was religious about torquing wheels to spec with the torque wrench step-wise in the star type pattern.

Discovered that the brake pads were hanging up slightly on the slide-ways of the caliper bracket, which unfortunately are cast as part of the whole spindle. The draggin was not enough to be noticeable or cause the car to pull to either side. The hanging up was caused by the pad shoe digging into the slide-way upon brake application. Eventually the rut caused by the digging action would not allow the caliper piston to retract normally after brake release - causing the dragging.

Finally discovered what it was after the right front locked up after a brake application and would release until after I put it in reverse and backed up a bit to cause the pad shoe to release off the ridge.

Didn't want to buy a new spindle, so ground the slide-way on the spindle slightly to remove the ruts. Been working fine - and with no pulsation - for 6 months now.

Keep us posted on what you find.