Brakes soft after changeing both front and back.

[michael hurd]

I bleed with another person, and open the bleeder screw only after the pedal has been pumped a few times ( 2-3 times ), and held down. Once there is steady pressure applied, open the bleeder and close it as soon as there is no more fluid.

Keep an eye on the level in the master cylinder to make sure that it does not run dry during the bleeding process. Add as required. Take the vehicle for a drive after bleeding all 4 corners, and if it's still spongy, then repeat the hard braking / ABS activation and bleed the brakes again.

 

[77Impala]

OK, I have re-bled the brakes, in my driveway. This time ABS, RR, LR, RF, LF. They feel much better at the moment. I will be using the truck tomorrow and will see how they preform. I also tightened the parking brake but now need to find a new actuator unit. I have been having trouble with the unit for the last 2 weeks, the pedal springs back when it chooses such as closing the door. That is not good IMO for a manual tranny vehicle. Looked at it and did not see a way to fix the current unit. LMC has one but I will try locally if I can.

If the pedal is still soft tomorrow I will have to wait for a warmer day to take it down the gravel driveway of my job to re-bleed them again.

 

[77Impala]

Very much improved. Had been pushing so hard the last 2 days that I had to drive in for a bit to see just how the pedal was during braking and holding. It is back to normal. Thanks everyone for your help on this.

Now to find and replace the parking brake actuator unit.

 

[AbramF_496]

Hooray!!


Sent from my iPhone using Tapatalk

 

[77Impala]

After a few days I found that the system still had air. Could not get the RWAL unit to activate. Long story short I removed the RWAL computer and valve unit. Re-routed the rear brake line to the brake pressure sensor valve. Nice very firm brakes, much firmer than before I had to change the pads/shoes and rear wheel cylinders.

Here is a link to a thread on this forum in deleting the RWAL ABS system. Only thing I did different was to cut and tuck the OEM harness wires so there is no evidence of the system being there.
http://www.gmt400.com/forum/showthread.php?11427-1990-C1500-ABS-(RWAL)-removal

You must be registered for see images attach

 

[bigfutz]

My brakes are getting soft and are probably past due for general maintenance anyway. Lots of good info here that I’ll be able to use. Thanks all!