well i just got a 01 4x4 6sp a couple of weeks ago dodge cummins . And the fella i got it from is a good friend of mine all stock except straight pipe. He told me he had all of the breaks redone which i now i can believe him but he also told me they act weard which he is definately right whin i slow down to about 10mph i can feel the pedal get real stiff and feels like the abs is bumpin it will stop but after the bump feeling it will almost send ya threw the windsheld any ideas thanks..

 

its just one big jolt?? not like repetitive...if it were more then one i would say the rotors are warped but...

 

its nothing like a warped rotor it seems to be like some prob with the abs its self brakes fine at high speeds only shutters on my break pedal at low speed an pedal is extremely stiff at that time . sorry about my spelling not a real good typer eather so what ya think??

 

Mine has a similar prob. Hit a bump and I here a noise under dash/hood and the pedal is stiff. Shortly there after the abs and brake light come on. Then the brakes function "normal". (ie. no stiff pedal or noise)

 

any codes on this??

ABS can be a pain

 

Here is some information and a bit of schematics to aid your chasing...
ABS Failure

Now if your speedometer is working properly and the speed is correct then most likely your rear sensor is fine. But now the 2 front ones could give you troubles. If iether one is bad it will make the pedal feel hard then let go and the ABS computer will fail. At this point the ABS is no longer working.

But if the pulsing is felt constantly I would say it rotors.