I could use your help?

[78Brougham]

The primary shoe is the shorter one it goes toward the front, the secondary is towards the back.

 

[saylor]

ya what homeboy said the lead, lag shoe.. it does matter which one is which.

 

[66SportFury]

How did you make out with this issue? Did you bypass the PV just to test if that's the issue? The other test I think you should do before bypassing the PV is a pressure test. You'll need to buy or borrow a brake pressure tool. Test the rear pressure and front pressure. You should have when you press on the pedal with normal force between 1000 to 1200 psi in the front and if you hit the pedal hard (panic) it can go up to 1400 psi or more. The rears should be between 600 to 700 psi. The other thing is and I'm sure you did this already, did you remove the stock PV? Also do you have the PV after the distribution block just going to the rear brakes? What ever you do, don't leave the PV out of the system. The rear brakes can lock up from to much pressure. You should have it setup with no distribution block with the line coming out of the master cylinder going to the PV and then to the rear brake line. The front brake line out of the master cylinder should go to a distribution block or just a simple splitter. If the car stops using the EM brake while driving, then to me it sounds like you're not getting enough pressure to the rear wheels and the only way to test it, is to use a brake pressure line tool. They're not to expensive. $50 for the cheaper ones and they go up from there. It's the only way to do it so you'll know how much pressure is at the rear and front. It's simple to do. Unscrew the bleeder on a wheel cly and screw in the gauge,..then press on the brake pedal (with normal force not panic) and read the pressure at the wheel cyl or caliper. That's it..! If you getting a low reading at the rear, there's either a blockage, or the PV is bad. It could also be the wrong bore size master too. Have you checked the rear flex hose? It could be bad,.but before replacing anything,..do the pressure test. Sorry for the long post..!