trouble getting a brake pedal 1990 Chevy RWAL

Mr. Smith · January 10, 2006

My buddie has this truck. He put shoes and pads on it 2 weeks ago. In short order the brake pedal pretty much went to the floor and wouldn't stop. So he bought a master cylinder and we changed it and flushed the brake fluid out. The old crap looked like tar.

He broke off a bleeder in one caliper so he replaced it. The truck had a horrible pull so he replaced the other one and the pull went away. But still a horrible pedal with vacumn assist. With booster bled out it is much better but not that great.

The master cylinder sloshes back alot of fluid out of the big side of the reservoir. I dont think the master cylinder is very good. I also heard of the rear ABS modulator causing this low pedal crap. Any suggestions?

Thanks in advance.

GM-Tech · January 10, 2006

The master cylinder sloshes back alot of fluid out of the big side of the reservoir.

Not sure what this means. When? Also, on the RWAL system, it wouldn't be unusual to have a bad dump valve, which can cause a very low and soft pedal. The dump valve is that silver cylinder looking thing below the master cylinder.

redvett · January 10, 2006

You should never do a brake job until the RWAL or ABS brake system has been flushed to get all the dirt mosture out of the system so it does not plug up the valves in the system. Cheaper to flush than replace the valve systems.

Mr. Smith · January 10, 2006

You should never do a brake job until the RWAL or ABS brake system has been flushed to get all the dirt mosture out of the system so it does not plug up the valves in the system. Cheaper to flush than replace the valve systems.

<{POST_SNAPBACK}>

I agree with what you said there. I tried to explain to him but I guess the message didn't get through. He is having to pay the piper at this point I'm just trying to help him out.

Gm-Tech... WHen you apply the brakes alot of fluid is sprayed up from the inlet side of the reservior.

Thanks and I will post up what is found...

Mr. Smith · January 12, 2006

Today after putting a new master cylinder from Advance and taking off the POS reman unit problem is fixed. The pedal is very good and you barely have to touch it for great stops.

Now I will go back and help him fix the other things he attempted to fix. He means well but needs a good mentor.

Word for the wise... Don't waste your money on reman units from Advance. Save the hassle and buy a new one. For what it's worth the ABS code is now gone. Hmmm, not sure how that happened.