E-brake issue: constantly needs slack taken in

I have a strange issue with my e-brake. When I first pull the lever, it barely applies the brake. So in neutral, the Jeep will roll forward on the slightest decline. 

I can tighten it up by releasing and pulling it 3-4 more times, but then it becomes just as loose as it initially was after driving it for a short distance. I have 87k miles and replaced the rear brakes at 70k, but didn’t replace the ebrake pads at that time.