About a month ago I did my brakes all the way around (calipers,pads,wheel cylinders, and shoes. Well on the forth July I went wheeling and my rear brakes started grinding, after closer inspection I found out I must have been driving that whole month with them locked up. Today I replaced my shoes and wheel cylinders again. When I go to bleed the I am getting veyr little pressure (The fluid only shots out about 2 inchs or less) and is not consistant every time. If i take the wheel cylinders off the and step on the brakes the fluid shoots out of the lines about 6 foot. I have tried gravity bleeding them. 1. open both bleeders. 2. take top of M/c 3. Keep a close eye on the M/C and make sure it has fluid at all times. 4. let drain for a while getting about 2-3 M/c full of fluid through the lines. 5. Close the bleeders. 6. reinstall the mc/ lid. but have still no strong pressure with wheel cylinders on. The pedel is spungy the whole time and goes all the way to the floor. I checked my fronth calipers and the spay like old faithful so the front are fine. What should I try next?