On 25 Nov 2005 20:59:30 -0800, firstname.lastname@example.org
>> Hello all!!
>> I have a 2002 XLS 4-door 4WD with 55k miles. Recently I noticed that when I
>> press the brake pedal to stop the vehicle, just before the SUV comes to a
>> stop (maybe 2-3 seconds before) -- ...there is a feeling of a thump or a
>> light jumping sensation from the rear as the vehicle comes to a stop. This
>> is happening during the time I am modulating the pedal and slightly letting
>> up on the pedal just slightly during the last couple seconds of applying the
>> breaks before coming to a full stop (letting up on the pedal slightly to
>> come to a smooth stop.)
>> The brakes have all been replaced 4 months ago, and there are new tires
>> installed 2 months ago. The rear diff was also serviced on TOC from Ford as
>> well as the both rear wheel hubs replaced on TOC.
>> Any ideas?? I checked and all the calipers are on correctly and everything
>> is on tight. Could this be a bad caliper??
>> thanks for any advice!!!
>Warped rotors come to mind- I'm guessing that the 2002's have rear disk
>brakes. I read somewhere recently that this is a common problem with
>disk brakes on many models. The lugnuts have to be torqued properly or
>the rotors warp. If the lugnuts weren't put on tight enough when the
>tires were changed, this is a possibility, though I would think the
>front wheels would be more prone to this problem since they work harder
>and get hotter.
I *think* that warped rotors cause a pulsing vibration related to car
speed, not the one thump.
My older one has an expansion splined joint in the drive shaft which was
never lubed properly, and in medium to warm temps, I get that bump just as
I stop, and just as I start out again. Instead of sliding smoothly, the
joint hangs up, and then "gives" making the thump.
The only reason some people get lost in thought
is because it's unfamiliar territory.