Brakes.. an almost violent jerk when I use brakes...

What is your question?

98 Jeep Wrangler sport 4.0 standard. When I use my brakes sometimes there's an almost violent type of a jerk. But it doesn't jerk to side (like it would if it was a brake pad grabbing). It feels like it's coming from the drive train. But I'm no mechanic at all

What makes this problem better or worse?

More noticeable when it rains

How long has your 1998 Jeep Wrangler had this problem?

On n off, about 6 months. Is getting worse recently