Rear Brake Problem 2000 Cherokee

On my dirt driveway applying my brakes causes my left rear tire to dig a trench into the dirt, the other three wheels stop normally. On the asphalt breaking cause the vehicle to pull to the left. Does anyone have any ideas of what the problem is and what to look for?
Thanks,
Bill

I suggest disassembling the rear brakes and seeing what the issue is.
It will provide more useful information than our guesses and eventually it is going to have to be done anyway.

I had the same issue.I recommend rebuilding the rear brakes. Rock auto has a package deal on a kit. Wheel cylinders, springs, shoes, drums, etc... do one side at a time and take pictures of each before you start. It'll help you get them back together correctly.

I think I found my problem. As soon as I recover from jacking it up and rotating the tires (prior surgery problems and bad back) I'll take it off of the jack stands torque down the lug nuts and take it for a test drive. The cable on the automatic adjuster had snapped and the part of the cable with the spring had dropped down under the shoes, plus the adjusted arm dropped below the shoe due to the spring.