Trying to fix brakes

[Johnnyz453]

So iv had my truck for a few weeks now and wanted to get the brakes stronger. Right now they dont stop very well. Tonight i bled all the brakes and it still didnt change anything. The brakes have pressure and there is no air in the lines. Has disk front and drum rears. I did two vaccumbooster tests that i read how to do online and it seemed fine. Dont know where to go from here. The pads in the front look like they still have 50% left. The truck doesnt pull to one side. The right rear drum makes a squeek everytime you press the brake pedal down though.

 

[Georgeb]

If you have good shoes on the back try adjusting them up a bit. You want to go up to the point they just rub the drums slightly.

 

[chengny]

I did two vaccumbooster tests that i read how to do online and it seemed fine.

That only tells you if the power assist is well...assisting. Power assisted brakes are only meant to decrease the effort required by the operator when the brakes are applied. A healthy male adult should have no problem stopping a vehicle without power assisted brakes. It basically boils down to being able to using just your toe as opposed to the ball of your foot when braking.

What a test of the power assist unit (vacuum type, in your case) will not tell you is anything about the internal condition of the master cylinder. The pressure developed by the MC is dependent on the condition of the piston seals and cylinder walls. Worn rubber seals or a scored/pitted cylinder will render the MC useless - even with all the power assist in the world.

As the brakes are applied - and the piston moves forward, the brake fluid just leaks past the seal/cylinder wall interface and causes a marked decrease in both flow and pressure at the outlet ports.

If you are sure that your lines are properly bled, and the drums are adjusted to spec - I would next check/change the master.