What have you done to your 1st gen Tundra today?

No. Rear disc. Happiness. If I did a rear end upgrade it’d be a landcuiser full floater.

 

I was just trying to be obnoxious, I am totally following the disc conversion.

I am also feeling a little left out of the fun as I stockpile parts for the return of my project truck. For now she sits in time out waiting on speed freak bandwidth for the water pump and alternator.

 

Seams fitting for the 2UZ-FE.

 

Nice, I’m only 10k above you on my 06

 

And I’m only 10k above you on my 2000!

 

Hit 170k today

 

Yeeesh...

 

Been there, done that. Good luck getting the old one off. I had to cut the studs and grind it flat to use new through bolts...or you could remove the bed.

 

Customized my interior.

 

Yes, I'm expecting a fight.

 

Drove my truck today and realized my frustration with the mushy pedal is reaching a boiling point. I actively avoid driving the truck most days and take the Rav4.

@jpink was riding with me last week and noticed me double pumping them to build pressure. I'm going to try to burp the ABS system a few more times. I really don't know what else it could be. Sometimes when the ABS is acting up the pedal gets real firm for a few seconds, almost like it's pushing the air back out. If I could figure out how to remove ABS all together I would.

If Heather sees this and wants to give me shit, that's fine.

 

Double dog dare heather. Otherwise, sounds like a leaky system. Look for drips while hard standing on the pedal. ‘Release’ pedal slowly to allow bubbles to form. Which would be a seal, if its tighter while short stroking.

 

Wouldn't I be losing fluid in the MC if I had a leak?

 

If your not loosing fluid I would assume the diaphragm in your brake booster is failing.

 

Good to know. When I did the booster test that's in the service manual, it passed. Could it also be a bad check valve? I've never seen any member replace theirs.

 

If you have mushy or spongy brakes with no sign of leaking and you are certain the lines are air-free you probably have a bad internal seal in your master cylinder.

Here's a random image to show you what I mean:

 

Absolutely, I’ve never seen this on the forum either, but definitely could be a failed check valve allowing a bleed through.

looks like they are cheap and easy to replace. If your brake booster passed the service manual test then I would try this next for sure.

 

Did you find a video? I searched the FSM and the only thing that comes up is the bracket. It's to the left of the MC?

 

It's on your brake booster. The plastic nipple with the hose coming off of it. Upper left in the diagram.

 

get intimate with the hose that's part of check valve and give it the ole suck and blow test….turkey baster for the blow works wonders.

 

I was just about to report that I did this test a few minutes ago and it passed. On to the next theory.

https://itstillruns.com/test-brake-booster-check-valve-7502988.html


@Desert Dog This has been a 10 month saga. Before you joined they thought it was possibly my master cylinder so I replaced it and the problem remained. I guess it's possible that the new one I bought is bad but I really don't think so. The fact that I can pump the pedal and build pressure makes me think I'm likely compressing air. I just haven't been able to get it all out. I really wish they put a bleeder valve over on that damn ABS module.

 

Ahhh. I just read this again. I actually wasn't able to suck any air out. It doesn't specify if the truck should be running. Would that matter?

"Suck air out of the hose. If the line is not blocked and the check valve is functioning properly you should be able to easily suck air out of the hose."

Well, well well...

 

Yeah, PCV valves are checked the same way or any check valve for that matter !

 

I edited my post while you were typing this. Does it matter if truck is running or not? That link doesn't say. If I can't suck any air out, that might be a problem ey?

 

I hope that’s redemption I smell!

 

Personally, I have always had a check valve in my hand and tested it that way, so no you don't even care if truck is running.

 

At this point I'm so jaded that I won't believe it until I see it. I have tried literally everything under the sun to fix this and I stopped mentioning it after Heather hurt my sensitive feelings.

 

Haha I’m sure you’ve done stuff and not said anything to keep the shade from being thrown from Heather’s way.
If this is it, I think we should all send heather some hand lotion.

 

I just went out and removed it completely and did the suck and blow test(insert joke here). It passed. I can't blow air into it but this time I could suck air through it. I have no idea why this would change from before when it was still in the booster. I also checked the hose and it's not blocked.

 

Understood. I began to understand your situation more after I had seen that you had posts on the subject on multiple threads. When the entire brake system was functioning and you tested the brake booster, did you do that with the engine running while you depressed the pedal? You'll know the booster is functioning properly if you feel the system pressurize and the pedal kinda kicks back. If you didn't feel it kick back, that's where your issue is, the booster. At this point though, I may consider letting a shop try bleeding the system if I hadn't been successful just to be sure and to relieve any frustration on my part and have my truck safely drivable. Having said all this, it is possible the MC does have a bad internal seal. Just something to keep in mind. There's only a few things that will cause what you're describing (i.e. mushy brakes with no fluid loss): Bad booster, bad check valve, bad MC or air in the lines. If you've tested each component properly and ruled them out one by one, the one you're left with is the culprit. Keep us posted.