On going problem with the brakes on my truck. Started with a leak in the line. Since then husband has replaced the line, master cylinder, and both rear cylinders.

The problem we are still having is there is NO brake peddle. None at all! With engine going, or without, there is no pressure building up.

The rear brakes, when he replaced the rear cylinders, were all black and gunky. They drained ok. Once he put it all back together and was ready to bleed the brakes, nothing came out. We have since let it gravity bleed, we have taken the advice of the local brake shop and tried to force them by "stomping" on the brakes with the bleeder screws open. This resulted in a fairly good bleed, but we still have no built pressure, and definately no brake.

We have no idea where to go from here. We are running out of ideas and money. We don;t want to take it in, as we never have had to before, and quite frankly, don't trust anyone around us.

 

there's 2 proper ways to bleed depending on which ABS you have, but both involve tricking the combination vale into opening to the back, and also running the ABS module to bleed air out of it

 

Rock, did he bench bleed the master cylinder before he installed it?

 

The way he bleeds them is to have me pump the brakes 10 times, and hold it, then he releases the pressure on the bleed screw. He closes it back up and I pump, and hold again. We repeat this till he is satisfied there is no more air. This is how he has always done them.

What other way is there?!

 

Yes, he did this for 30 minutes straight. Probably more than 200 compressions (is that the proper term?) There were no air bubbles at all when he put it in. He rebled all brakes once the master was installed. This is when he noticed there was no change in the brake peddle.

 

How reasonable would it be to start at the front and go through all of the lines, the brakes, and clean everything out? Can we use an air hose and blow out the lines from the split in the back where it goes to the rear brakes? Obviously we would have to rebleed the lines.

Just not sure what else to do! Does anyone have a brake diagram for the truck? This is something he can not find. We have the book on it, but it doesn't give a good diagram.

~ from my husband

 

There's no need to use air. Just use brake fluid. Actually, you start from the back as far away from the master cylinder as you can and work towards the front.

In regards to a diagram it varies as to what version of ABS you have.

Is it rear wheel only ABS or 4 wheel ABS? If there are wires going to the front wheels, along with the brake hoses, it is 4 wheel.

If it's 4 wheel ABS he'll likely need a DRB (dealer tool). The pump has to cycle to get the air out.

If it's rear wheel ABS - here:

MANUAL BLEEDING
(1) Remove reservoir filler caps and fill reservoir.
(2) If calipers, or wheel cylinders were overhauled, open all caliper and wheel cylinder bleed screws. Then close each bleed screw as fluid starts to drip
from it. Top off master cylinder reservoir once more before proceeding.
(3) Attach one end of bleed hose to bleed screw and insert opposite end in glass container partially filled with brake fluid. Be sure end of bleed hose is immersed in fluid.
(4) Open up bleeder, then have a helper press down the brake pedal. Once the pedal is down close the bleeder. Repeat bleeding until fluid stream is clear and free of bubbles. Then move to the next wheel.

PRESSURE BLEEDING
Follow the manufacturers instructions carefully when using pressure equipment. Do not exceed the tank manufacturers pressure recommendations. Generally, a tank pressure of 15-20 psi is sufficient for bleeding. Fill the bleeder tank with recommended fluid and
purge air from the tank lines before bleeding. Do not pressure bleed without a proper master cylinder adapter. The wrong adapter can lead to leakage, or drawing air back into the system. Use the adapter provided with the equipment or Adapter 6921.

 

To bleed in correct order for rear ABS only first is passenger rear then driver rear then passenger front then driver front always in that order. I will say check the service manual to be 100% sure that’s correct.


Rear is always first