Good feedback. I think it's easy to read my first post and assume I'm reckless for continuing to use the brake system as it was for this last year (aside from that fluid flush and pad change), but aside from this episode yesterday, the brake system behaved relatively normal. I'll revisit the rotors and swap them out too.

 

Be sure to check your caliper pins while you are in there. They could be sticking under extreme conditions... It's the only thing in the system you haven't mentioned and can be a problem.

 

Good advice. Frozen pins will reduce proper braking in extreme conditions, but, will not show up, as much, during minimal braking conditions. The caliper is suppose to float, meaning, it pulls and pushes the brake pads while braking. If it is only pushing, you don't get the proper clamping affect on both sides of the rotor surface.

 

Cool cool! I happen to have a new set of pins here.

 

If the old pins are gunky you should clean out the holes before you put the new pins in...

Had it happen before where I cleaned the pins and put them in the holes but they failed again in a few months,

lots of grime can accumulate in there so be thorough and you should be fine.

 

Update - I installed brand new OEM rotors, brand new LR pads, and completely tore down and rebuilt all four calipers. Even painted them! (satin black, no racer red here, thank you.) So fancy now. And I flushed a half gallon of brake fluid through the system. I power bled using the Nanocom, then bled the modulator, then bled the entire system again using the Nanocom.

After all this, I hopped in the car, and the pedal went straight to the floor. Awesome. SO much worse than when I started this whole project. Really felt great.

So, I picked my dramatic self off the garage floor, did some research, and thought, eh, maybe another source of my struggles is the master cylinder. So I replaced that (had a spare in the parts inventory), bled bled bled, no change. Swapped out the brake booster with another - no change.

I'm at a total loss. The brakes needed to be replaced anyway. They were super crusty, so not a loss there. The master cylinder and brake booster were parts I had on-hand from a donor Disco, so no loss there either other than time.

Some ideas - a few days went by with the calipers off the truck (they were a bit rusty so dropped them in the electrolysis tank and painted) which means the brake lines drained a lot of their fluid out. The brake fluid reservoir was pretty empty. Is it possible that I NEED to do at least some bleeding via the wife-in-the-drivers-seat method before using the Nanocom? Is that my problem?

FWIW, I hooked up a vacuum gauge to the little port on the manifold and it sat at a pretty steady 20". I don't think I have a vacuum issue, but not sure how to rule it out completely. Tips appreciated.

Also FWIW, before swapping in the master cylinder and brake booster, the brake pedal went to the floor with the engine off. Now it gets rock hard after a few depressings.

 

Bleed the old fashioned way, it may not fix anything but you can visually confirm the fluid coming out with each press. After bleeding each corner ask your wife if the pedal firms ups.

My rule is at least 3 goes around

Also will it firm up if you pump the pedal.

 

Yep, while driving it firms up if I pump the pedal. What does this mean again? Bad MC?

 

@Brandon318 it could be a simple as air in the lines or a bad master. The firming up is the key that is typical of air or a bad master cylinder, hydraulic clutches do the exact same thing with air or as they are failing.

 

Gosh... I'm just like... I've bled a gallon through this system today, and what are the odds of two bad master cylinders? I guess I'll try manually bleeding tomorrow and then go from there?