95 k2500! No brakes! Help please!

1995 Chevrolet K2500 Ext Cab 5.7L 350. Bought the truck and it has 240K miles so I figured I would put brakes on it. I put new front rotors, calipers, pads, and rear shoes, springs, adjusting screws, and wheel cylinders. The rear pass side brake shoes would not seat up completely, found the parking brake was stuck, so we cut the cable to the parking brake on that side. The rear drivers side parking brake cable seemed ok so we left it. The brakes feel as if they are possibly dragging and I have to pump the brake pedal several times before I can build enough pressure to stop. Also, the red parking brake warning light comes on when I hit the brakes. Any ideas? I bled the entire system. The owner said he put a new brake booster on it, but I'm not sure how long ago. The master cylinder looks like its leaking at the rear because the bottom of the booster is wet. So i purchased a new master cylinder, but I have not installed it yet. Any suggestions? Does the ABS pump need to be bled? Master cylinder? Booster? Any help is appreciated!

The master cylinder is deffinatly leaking, you should replace it as next step. The current problem is there is still air in the lines somewhere. As you pump them several times this compresses the air and gives the feeling of more pedal. Thus the spongey feeling. ....replace master cylinder, bench bleed very well before installing it. After the install, grab a clear glass container half full of dot 3 fluid get a piece of 3/16 vac. Hose put one end in glass container, starting with the right rear wheel put the other end over the bleeder screw and loosen one turn. Have an assistant pump the pedal slowly until air is no longer presant tighten bleeder and remove hose, continue the same in this order left rear-- then right front and finish with left front. And repeat if still not satisfactory. It may take several times. In most cases the abs does not have to be bleed unless the abs unit itsself is replaced. The order in witch the wheels are bleed is a critical order.

ok thanks for the reply. what about the parking brake light? i've pressed and released the brake several times. and like I said earlier, the pass side cable is cut because it was sticking and the drivers side seemed fine. what would cause the light to come on? I thought if it was part of the ABS part, the amber light would come on? Is the master cylinder causing the brake drag, pedal problem, and the parking brake light?

The system has a presure sensor in it, this is the cause of the red brake light. When there is air in the system the pressure is not correct and the light will stay on, cobination of air in system and maser cylinder. And the drag may be due to miss adjustment of rear brakes, there should be just a little drag when drum turned by hand.

i thought the pressure sensor would cause the amber abs light to come on? not the parking brake light? so is the booster out of the question?

the red light is for low brake fluid, low pressure and the e-brake warning.
the amber light is for abs only. and the booster only assists in brakeing. the problems you have described is classic air in the lines. it can be very difficult to get the air out of the system sometimes. i been doin auto repair for 19 years now. and the bleeding procedure i described before, is deffinatly the most efficiant way to bleed them completely. short of takeing it to a garage that has a pressure bleeder, witch can be expensive.

ok update on what happened today. I installed two master cylinders, one was bad so i had to get another one, bench bled it, then bled the entire system (3 times actually). pressure comes up a little bit and the red parking brake light went out but the pedal still goes to the floor with moderate pressure. you can pump the brakes a few times before coming to a stop and it will stop normal but you shouldnt have to do that. you should be able to hit the brakes one time and it should stop. i pumped up the brakes with the key off and started the engine and my pedal sinks so i know the booster is good right? only thing i know left in the system is the ABS pump? Could that be it? Does it need bleeding? theres nothing really left in the system. heres whats new on the truck. master cylinder, front brake lines, front rotors, front calipers, front pads, rear brake lines/hose, rear shoes, rear brake springs, adjusting screws. basically the only thing not new in the brake system is the ABS pump, brake booster, and front rubber brake hoses. Nothing is leaking though externally because there is no fluid loss or visible leaks. Any suggestions? the local junk yard has a ABS pump for $50. Think I should put one on it? let me know. thanks

you still have air in the system ...bleed again start from the rt rear lft rear rt front , and lft front ...

when bleeding you must not pump the pedal fast,,,, slowly push down and slowly lift up ....

with the pedal high and hard open the bleed screw so small amounts of fluid comes out , not with a large stream..

this will reduce air bubbles being generated...


If you cannot pump the brake pedal and have it hold solid at that height you have a leak , or the master cylinder is bad..


you must then clean all spills and look closely for the leak...then if none the master must be replaced..

what could also be the cause is the use of incorrect or contaminated fluid...

it was the ABS pump like I thought. I put an ABS pump on this morning, bled the lines going from the master cylinder to the ABS pump and now it works fine.

it was the ABS pump like I thought. I put an ABS pump on this morning, bled the lines going from the master cylinder to the ABS pump and now it works fine.

if the abs caused a soft pedal , a pedal to the floor this means the unit was leaking...

yeah. It had to be leaking internally.

Hvining this problem with my 88. no visible leaks from master cylinder or abs unit. so i wont know if its the abs unit until i put a new master cylinder on lol.