Low Brake Pedal 03 Ram Van 2500

[edhunt0r]

I have been working on the brakes of this van and replaced the rear shoes, wheel cylinders and master cylinder and calipers. I can not get a good brake pedal, if I crimp off both front brake lines I get a hard pedal. This truck has dual piston calipers with the brake line going into the center of the 2 pistons and the bleeder is up top, so I'm thinking air is trapped in the bottom half. I tried taking the caliper off and moving it around while gravity bleeding but I can still not get a good pedal. Please Help
I am not new to working on cars, I've been at it for over 20yrs, but this one is really kicking my butt.
:VHOT::VHOT::VHOT::VHOT:

[alloro]

With new calipers and wheel cylinders it can be a real bear to get all the air out of them at first. Sometimes it's as simple as tapping the cylinder/caliper with a hammer to shake the air bubble loose as you're bleeding them. Other times I've had to let a vehicle sit for several hours (sometimes overnight) to give all of the microscopic air bubbles a chance to come together and form larger air bubbles. In an effort to narrow down the problem a bit further, only crimp off one of the front hoses and see if one side or the other alone makes the difference. You might find that there is a problem with only one side, allowing you to narrow down your efforts.