A few days ago my mothers Olds Silhouette minivan lost brakes…the hydraulic lines were so rusty they ruptured, sending brake fluid all over the place.
I have since replaced the brake lines with those salvaged from a mechanically identical Pontiac Transport at a local junkyard.
Tightened all the fasteners, filled up the resivoir, bled the brakes, and found no leaks.
BUT…
the brake pedal goes all the way to the floor with NO BRAKE PRESSURE.
It may have to be bled at the ABS. Sometimes the order they are bled in can be important, I think it’s rear passenger, rear driver, front passenger then front driver side. I know the last time I had brake issues with my Blazer I had to get the garage to cycle the ABS with their computer so I could bleed them properly.
A total loss of fluid like that probably drained the accumulator, the auxiliary hydraulic system that runs the ABS. You need to take particular actions to return the accumulator to the state it needs to be in before you can bleed the rest of the system, and that state (and those actions) is different for different ABS designs.