Hi, New to this board. F 250 7.3 diesel lariat crew cab 4x4, 2001 with 122,00 miles and has been excellent truck. Suddenly developed a wierd vibration (similar to driving over rumble strips in highway) when slowing from approx. 30 mph to 20 mph lighter vibration when coasting down, but you can feel it, and much more pronounced (heavy)with light brake pressure. Have been through the brakes a couple times, pads all good, new rotors, new calipre on driver side front. Took truck to a reputable independent garage, could not find prob. then tire shop rotated tires & spin balanced, then to another very good alignment/brake independent garage and they could not pin point the problem.Do not notice any prob. at highway speeds, only dropping from the 30 to 20 mph range. Has any one encountered this problem? Do not have any idea where to look next, except I did get a laser point temperature gun and it appears that driver side front rotor is running approx. 120 degrees warmer than the passenger rotor after driving the truck???? Any help/ideas would be appreciated.
C.D.Z.

 

Hello I have the same problem with my 2000 excursion 2WD. Did you figure out this vibration? Thanks!

 

Drop the drive shaft at one end and check for loose or binding u-joints.