HI all.
I am at wits end with my brake system.
About 3 years ago the brakes started to get spongy. Then a few months later, they went all the way to the floor.
I have replaced everything other than the ABS pump/valve. I bypassed the pump with unions, but it never was right after that. They have always almost went to the floor since I did that chooch job. Yesterday I tried to lock them up on a super wet backtop and they just went to the floor with no skid at all. I used to be able to do that 3+ years ago.
Is this the behavior of the bad valve body on the pump? I see it is a pretty popular option on eBay but I cant seem to find a lot on this issue out there. I think the trucks used a similar set up int he early 2000s too.
Help is greatly apprecaited. I am down to this last part...
Thanks

 

So you replaced the master cylinder and power booster as well? Did you replace the rear drums/shoes and wheel cylinders? New brake adjusters as well? You said everything... I'm guessing maybe not every little thing?

If the adjusters don't work you'll get no grab over time from the drums. Seems to happen when they get dirty and old. So again you said everything, I imagine you did completely new springs in the back, adjuster, all of that?

Did you bleed the combination valve? The combination valve itself has to be bled. Bleed the lines completely and in order starting from the master cylinder to the combo valve and then the wheels in order?

Food for thought.

 

Spongy is air in the lines, excessive pedal travel is usually caused by the rear drums not being adjusted properly. You could have a combination of both.