OK home on R&R brakes real soft while running but will pump up when off. Also while running if I put the pedal to the floor the engine idle drops... would this imply a bad brake booster? Thanks

 

OK... plugged the vacuum at the booster have brakes but a lot of force to apply them and pedal stays hard.... air in system or booster? Help please

 

It won't hurt to go ahead and bleed them, just make sure you don't let the level in the reservoir get down low. Is it still idling weird with the vacuum line plugged?

 

Idle is fine when plugged, bleed them numerous times,
now I don't know which way to go... MC. Booster, Bleed(ABS)

 

It still doesn't make sense to me why the pedal would be too soft when the booster is hooked up then. Are the brakes working fine? Something might be up with your brake booster.

 

no lights no nothing... just doesn't want to stop and peddle goes to floor... disconnect booster and its firm and have to apply a lot of pressure for it start going down and stop
.... so confussed

 

Try to listen to the booster at the floor. When it went out in my Jeep, I could hear the booster air escaping/flowing when I pressed the pedal.

 

I can hear something in the cab.... with the booster vacuum disconnected and I get a good pedal, would that eliminate air in the system?

 

The booster works off air. Vacuumed air. It's separate from the MC. If I understand you correctly, you have no brake pedal pressure when the boost is hooked up? The pedal goes straight to the floor with no restriction? Doesn't stop the truck? Look for a leak in either the rear wheel cylinders, or the front calipers. A leak will present itself even without taking anything apart sometimes. Speaking of fluid, I'm assuming your fluid level is fine?

If all of the above is fine, then a new MC would be my best bet. Your booster sounds like it is functioning properly

 

went ahead and changed the booster and MC... no leaks anywhere... truck will stop now... but pedal still will go to the floor... Have bleed(gravity, old school and reverse power bleed) got a hair better... now been seeing different things about this some say it has to be bleed by scanner other say it doesn't.... anyone know for sure? Thanks for the advice guys