If you replaced the two rubber lines in the front, look to
make sure you have the copper washers at both ends replaced.
(Should come as replacements with the new hoses).
ALSO,.. Make sure you don't have two of them stuck on one end
of the line. One can become stuck on the caliber side and, just stay
in place when you go to put the new line on. For that matter, I'd check
both ends of the line.

 

Thats what I am going to try today..Have you ever heard of a brake hose bolt on the back of the caliper being to long and bottoming out before the hose is tight...I dont know if it is that, but I am grasping at anything right about now..

 

Ok, checked the brass washers, and replaced the drivers side front hose, I thought it might of been bad..After a quart of fluid, the pedal still goes to the floor while the truck is runnning..I hate to do it, but its about time to throw in the towel and bring to a garage

 

Before you do that, why don't you return the MC as defective and try another first.

 

What brand parts did you use? Sounds like a ****ty, chinese part.

 

All parts were bought at Napa and Carquest

 

WHAT Brand? Even NAPA will sell ****ty parts.

 

I am going to change out the master cylinder again today, see if that makes any difference.. I figured when they say new at the parts store, The sh#t is good..

 

Defects get through whether you buy new or rebuilt. Of course it might not be the prob anyway. I didn't go back to recall what you replaced, but it could be any of the parts you replaced.

 

Ok, I replaced the brake booster today, thinking the booster was leaking while pushing the master..I rechecked the master and thats good. and the brake booster didnt make a difference..When I plug the line coming from the proportioning valve to the front drivers side hose, the pedal stays hard as a rock, both running and not running..Its hard to beleive that the second set of new calipers could be bad..