Four wheel disc brakes.

The parking brake will not apply enough pressure. They like to see the rear wheels lock and slide at the inspection station, and they still roll rather than lock tightly.

I've adjusted the rear drums, they are properly adjusted. Not sure what else to check given it's supposedly self adjusting. I found one thread that suggested replacing the pedal assembly but I'm not inclined to do that unless I know that's the problem.

Any ideas? I've searched around old threads but haven't found an exact solution.

 

The emergency brake shoes are not self adjusting. Have you had the rotors off and looked at the shoes? It can get real nasty looking in there. The shoe surface gets all rusty and pitted, the drum area usually develops a ridge which could hamper operation. I have seen numerous times where the lining of the shoe falls off. I would be more inclined to look there than with the pedal. If the pedal applies and releases, probably not your issue.