Brake problem

My sister-in-law's pick up truck is messing up whenever you push the brakes it feels like there's a pop and then the rest of the pedal pushes through . I checked the front brakes a push the caliper pistons all the way in and then receded and they seem like to move smoothly as anybody have any idea what this could be? Thanks for any suggestions on what to check. I'm gonna finish looking at the tears tonight they are soaking now because they are seized and I can't get the drum off...

 

master cylinder failure

 

If you have a popping of some sort it sounds like your rear brakes. You wouldnt have any sound like that if it was the master cylinder i dont think. Also, if it's the master cylinder you would be able to pump the brakes and they would stiffen up and work like normal... if they dont do that then it's probly not that. good luck!

let us know what you find in the back, i just got done doing my brakes but messed up something on the back passenger side. gonna have my friend fix it now... i hate doing shoes

 

Thanks for the replies. It's sounds kinda odd in the rear but as far as the sticking at a certain spot then popping is more of the feeling than a sound. I will def post what I find ASAP. I've never had a problem like that and I've never had rear drums that hard to get off. Going out now to fool around with it.

 

Well it took me a while But I got the drums off everything looked okay inside the rear I push the pistons all away back on the passenger and driver side in the front and reseated them . the pistons look like they moved okay so I put everything back together and tomorrow take it for a test drive and see if maybe got some corrosion out it . if not I guess I'll look at the master cylinder.



P.s.- I noticed nothing was lubed front or back mainly the pins for the front pads. Think that would cause the symptoms like I'm having?

 

I just noticed last night while finishing up my bell crank on one side is not sitting on the backing plate??? I didn't pay attention to how they were both positioned before I started . This doesn't seem normal. My bolts are were they're suppose to be and the parking brake works but I can get them both to seat against the plate while the brake is off any ideas?

 

Home was right master cylinder kinda
Fixed it haha... I wasn't getting any pressure to the rear wheels. So I started cracking lines all the way to the proportioning valve and then I started getting fluid to the rear wheels. If this starts up again I figure the valve is bad . Thanks for all the help! I hope this helps someone else also.