Brake Problem

[RHamill]

My brakes were all good until I had to make a hard stop behind some idiot drivers who couldn't decide where they wanted to go while I was on the way home from work. Anyways as I was waiting at the next light I had my brakes held just like normal, and the truck would move forward a little, so I hit them harder while at the light to stop the truck from moving, then the pedal eventually is on the floor and it's just getting to the point where it's dangerous to stop my truck while behind someone.

The truck has new rotors, elite pads, the caliper pistons are good, New drums, shoes and hardware.

Master cylinder is half full, so I have narrowed it down to what I think it might be.. leaky wheel cylinders, and I had my sister pump the brakes and I looked under the truck, couldn't see any obvious leaks, but i'm guessing wheel cylinders, the ground is snowy and it was dark, I used a maglite to look. I'll tear it apart tomorrow and take some pictures, hopefully I can find some place that's open I can get parts from, because I work at 7am monday and this is not something I want to deal with in this weather before work.

 

[dcZ71]

I just had a similar problem, had to make a hard stop to avoid someone and one my rear brake lines along the frame rail next to the gas tank started leaking because it was rusted out, its a common problem. Kind of a pita to replace though, gotta drop the gas tank to have access. Check those rear lines.

 

[RHamill]

I really hope its not.. Ill post my results tomorrow..

 

[RHamill]

Ok, so I bought the wheel cylinders, took the one that was leaking off (drivers side). Had no problems, then went to passenger side, saw that the bleeder screw was bigger, tried to remove the brake line from the wheel cylinder, and it wouldn't turn for the life of me, just the wrench turned and rounded off the nut. I soaked the hell out of all those bolts with PB blaster before I even went to the parts store to get the cylinders too. So I figured I would just do the passenger side one next Friday so I have the whole weekend to fix it and any problems that come with it.

Well I put the brake line back in the new cylinder on the drivers side and tightened everything up, began bleeding that wheel only, I know you should bleed both, but I've done it a bunch of times and very little air bubbles will still allow you to use your rear brakes [that was a little foreshadow to the next segment of my story here].

Well even after bleeding correctly 4-5 times, I get in the truck, start it up and the pedal is like a bowl of mashed potatoes.

I bled it all those times with no air bubbles, I pulled it out of the garage, hit the brakes and the front stopped and the rear kept on spinning on the ice even with the brake pedal on the floor. Master cylinder is full, no air in lines.

My conclusion is, maybe a ripped booster diaphragm, maybe it needs a new master cylinder because the hyper-extension of that push rod on the primary piston probably ripped a seal in the master cylinder itself.

BTW, remember all new brakes all around, rear are adjusted correctly, with a little drag, no fluid leaks anywhere.

Getting it towed tonight to a shop, Ive had enough of working on that damn thing.