Did you find that the fluid was kinda slow going through? When the LSPV is tied up so it see a "max" load it really lets the fluid go through there to the rear brakes. I didn't find my problem until I locked up my brakes the rears didn't do a thing.
It should be the left rear first...then right rear...then LSPV but I did my LSPV first because it didn't allow the fluid to git to the rear brakes. Yes...I had replaced my master cylinder first thinking that was the problem but after running it through my head...the LSPV became my focus.
I had to beat on it with a 2x4 to break any crap that was built up in there free and I got a lot of air out of there first...then the left rear got a lot of air out and the right rear was pretty much fluid. After doing the fronts, the pedal was fantastic!!
The test I did was block the front wheels then jack up the rears by the differential. Spun the tires and stepped on the brakes. My wheels were still spinning!!
After attacking the LSPV and bleeding it out, the rears stopped like they were supposed to...
