96 Explorer break issue

The front breaks on our 96 Explorer vibrate and grind LOUDLY when breaking suddenly or on ice. Is this normal and if not what is it and how do we go about fixing it.

Thanks!

I assume that on the pavement you do not have the vibration and grinding noise. If this is the case, there is nothing wrong with your brakes. It's the ABS (antiskid braking system) doing its job. When you brake on the ice the brakes lockup and the ABS thinks you are skidding and releases and reapply the brakes to help keep the vehicle under control. If you have this noise and vibration on dry pavement you should get a brake inspection. From what I can figure from your posting, it's the ABS that is working and doing its job.