I upgraded my stock brakes to 14" Baer rotors and stainless lines all around, dual piston SUV calipers in the rear, and 05+ Silverado calipers in the front, along with Wagner Thermoquiet pads. I did the rears first and afterwards the pedal was a little firmer than stock. I was happy with this result and was looking forward to what the fronts would bring. Then I did the fronts 5 days later and the pedal is now softer than stock.

I have to depress it 1.5-2" before it starts braking. Once it starts braking it feels pretty good. I bled all four corners until no air came out, and then some to remove old fluid. I flushed a total of 1.5 liters through the system. I used Valvoline synthetic DOT 3&4 fluid. I did the flushing with the engine off at first, then with the engine on. I never let the reservoir go dry, it never got below half full. The order I did was RR, LR, RF, LF. There are no leaks. The pedal was much softer after doing the RF corner, then remained about the same after the LF corner.

I'm concerned why it was better with just the rears done, and now worse with both the fronts and rears done....

 

Might need to have the ABS pump cycled. Air can still be in the pump and can cause a soft pedal. or you can find a dirt road and do some 25-0 mph stops lol.

 

Is this something that the dealer needs to do with a Tech II?

 

yes a dealer can do it.

 

Can only the dealer do it? I couldn't find any how-to's on bleeding the ABS unit.

One thing I did do while putting the rears on was remove the front brake line coming out of the master cylinder. For some reason I thought I could drain the reservoir this way. No fluid came out so I hooked it back up. But the brakes were better than stock after doing this, so I'm not sure if that was a cause.

 

pretty sure any high end diagnostic tool can do it so if you have a shop you like they can probably do it even if they don't have a gm tech II...

 

you can find a dirt road. And hit the brakes form a 25-0 a few times. That will activate the ABS pump and cycle it.

 

FWIW Not all high end scan tools can do this.

 

Yes, you have air trapped in the system. How far are you from say Orange county???

 

4ish hours from OC.

How does tripping the ABS fix the issue? The air will still be trapped yes? Or is another bleeding required after?