I have done the search. I have read "At wits end" http://www.oilburners.net/threads/brake-problem-at-witts-end.78362/#post-927148 and I have the same sort of problem. The truck ruined the right rear drum. Bought shoes, bought wheel cylinders (bleeders stuck, cheap enough, just replace) bought one drum. Other drum is serviceable. Before I started this the brake problem was there. Good firm pedal with truck off and vacuum booster drained of vacuum. Start truck up, push brake pedal and pedal slowly sinks to almost the floor. So I replace the shoes, free up the adjusters. Find the parking brake actuators are sticking. Free those up. Find AZ sold me two left wheel cylinders. So I will replace only one at this time. Clean, mount brake shoes, adjust shoes out until the drum will not slide on and then back off a few clicks until the drums will slide on. Bleed brakes. The low sinking pedal is still there when running. Replace master cylinder. Low sinking pedal is still there when running. Desperate now. Bleed RABS. Nope, no change. SO. Do I have the rear brake shoes mis-adjusted? Or is something else going on? I do plan to replace the right wheel cylinder, but I do not expect that to change anything. HELP!
That sinking brake pedal.
- Thread starter noddaz
- Start date
Golden Helmet
Full Access Member
These might be relevant to you: https://www.ford-trucks.com/forums/678376-brake-pedal-slowly-goes-down-tsb.html#post5387282 and http://www.thedieselstop.com/forums/f31/power-brakes-last-52122/
Just something I came across while trying to solve my own soft brake pedal issue a while back.
Just something I came across while trying to solve my own soft brake pedal issue a while back.
mooseracing
Full Access Member
Going through this now, but I had to do a complete brake system overhaul as I pushed them too far before doing routine maintenance.
I bypassed the RABS, same issue. After seeing the cost of a Zero loss booster, I'm going hyrdo boost.
I bypassed the RABS, same issue. After seeing the cost of a Zero loss booster, I'm going hyrdo boost.
Last weekend I replaced both drums, cylinders, and shoes and yeah at first I had a low pedal even though I thought I had 'em adjusted right. But a few more clicks on the adjusting wheel seemed to make a big difference. I gravity bled the fronts and used a couple "speed bleeders" on the rears. BTW the speed bleeders from NAPA kinda', suck--I had clear tubing on the bleeders to catch the waste and I could watch little air bubbles slowly get sucked back up the tube.
Even with newer calipers, rotors, pads, all new rear brakes, and new vac pump the stopping power is not impressive. It's a shame Ford didn't Hydroboost these from the start.
Even with newer calipers, rotors, pads, all new rear brakes, and new vac pump the stopping power is not impressive. It's a shame Ford didn't Hydroboost these from the start.
Golden Helmet
Full Access Member
That's what I did, even good vacuum brakes are going to be spongey. Hydro boost fixes that, and you'll have brakes that are actually GOOD
Ok, nothing to report yet. Installed the booster and pumped the brakes with the truck off to test the pedal. And blew out the right rear brake line. Fabbed up a line, installed it and called it a night because of rain. Came back next night, bled the brakes. And I was testing the pedal before starting the truck and......... Blew out the left front brake line right where it hangs out in the breeze because the rubber splash shield does not quite cover it from the the crud the front wheel throws up. *sigh* Fab up that twisty curvy line and install it. And I will try to bleed it tonite...
