Little bit of help with brakes, please

Still having issues with brakes, replaced and bench Bled MC bled right rear, LPV, Driver side rear, passenger, front driver, Break goes all the way to the floor When engine is running. when engine is off brake pedal slightly mushy, but I cannot get any more air out Possible right caliper stuck on passenger side now when put into drive it just rolls even while fully compressing breaks need help

 

Try bleeding the rear and the lspv again, but with the truck running.

RR, LR then LSPV.

Then the fronts.


If you still have air/soft pedal, you could have a bad master cylinder. Where'd you get it?

 

Got the master cylinder from O’Reillys I got a brake booster just for in case contemplating Getting upgraded front calipers also just in case this is also a tomorrow problem

 

I wouldn't drive it yet if the pedal goes to the floor and the truck still rolls

 

If it keeps going to the floor after rebleeding it, it could be a bad part out of the box.

 

Friends don’t let friends buy Toyota parts at O’Reilly.

 

This ^ Was the master cylinder you bought aluminum or steel? Was it new or rebuilt? Guessing it was rebuilt. They hone out the valve body and put new seals in. Sloppy as fuck. Been down this road. Buy a factory one. If you’re dead set on aftermarket, buy new not rebuilt.

 

This ^^^

This is why we don't buy aftermarket parts. Especially not from O'reilly, the place is a fucking cesspool of shit advice and shit parts.

And it's also possible that OP didn't bother with making adjustments to the pushrod, or bench bleeding the MC (if necessary). Or did something silly like pushing the brake pedal all the way to the floor while bleeding, and blew a seal in the MC.

 

I've had bull from advanced and oriellys so not much difference didn't have time to work on it currently working on aeronautics finals

 

@assassin10000 just in case do you have a pdf on the bleed procedure or good to know info

 

Is this the same issue you’ve been having since April 2024? 2 years this truck has been sitting with wonky brakes?
When was the last time the brakes operated as normal? And what was the event that led to this issue?

 

Nope. Just what is in the FSM.


That and I know sometimes it massively helps to have the truck running to bleed the rears. The booster assist really helps push fluid past the LSPV and bleeders.

 

@TYTA7 no it had semi working breaks it hasn't been sitting but just had to take it easy

 

Are you having issues with your 2012, or do you have a 2000-2006 Tundra like the rest of us here in the 1st gen subforum?

 

So because I don’t own a 1st gen I’m not welcome here? K.
Brakes are brakes my friend. I also worked on cars professionally for nearly a decade… all different makes and models.
But I’ll leave now. Good luck.

 

Everyone is welcome, and certainly if you can add something to help OPs problem out. Has nothing to do with what you currently own. Not sure what the previous comment was about.

 

Cool, then you know your 2012 doesn't have the LSVP our 1st gens do, which has a ton of impact on how the overall braking functions in the 1st gen trucks versus other gens of the Tundra. It's the main reason I'm bringing up the year range, my friend. There are differences between generations that are, frankly, substantial, so it's pretty important to clarify.

I've worked on cars and farm equipment dating back 40 years. You're in good company.

I'm sorry you've come to that conclusion with zero evidence to support you arriving there. That's on you, bud.

Everyone is welcome here, the only thing any of us would ask is to leave your attitude and the chip on your shoulder at the door.

Actually ... we also prefer folks leave their drama/trauma at the door, too. No room for any of that amongst adults.

 

I initially misread his 1st sentence as, "this is the same issue I've been having since April 2024". That was my mistake.

Y'all know me, I try not to be a dick. I do my best to clarify things when I see relatively new folks with low post counts pop into 1st gen, just because our trucks tend to be so different.

Having a dramatic reaction over my reading comprehension, I feel, was his mistake.

 

All fair... I'm not having issues with my truck.

Was just trying to help...
My questions were to help establish the history of the issue, to me that is always my first step in diagnosis.
If we can establish when the issue first started, and if there was a specific repair or event that started the problems, that's where we need to look.

As an example... back when I was wrenching, a customer brought their truck in (an old ford ranger) with spongy brakes and unable to get a solid pedal.
After talking to the customer I found that the problem started when he replaced the calipers himself because one was dragging...
Upon inspection I found that he had installed the calipers on the wrong sides so they were upside down (bleeder screws on the bottom of the caliper) so it was impossible to get all the air out of the calipers.
Swapped the calipers, standard bleed, good to go, sent him on his merry way.

@OP what all have you replaced at this point? This is obviously a long lasting issue so take it back to the beginning... what was the original problem and what all has been replaced?

 

@assassin10000 @TYTA7 2000 tundra normal nothing “major” brakes that’s pretty much it currently replacing mc soon to be calipers

 

I'd toss out a bit of historical here to help you with potential diagnostics. 2000-2006 have some very specific quirks with braking, and common fail points. We have a sticky thread to help folks diagnosing this stuff (link).

Some of the big follies we see:

• The rear brakes are pivotal to proper, non-sloppy, non-squishy braking; by default, the rear shoes are supposed to auto-adjust to the correct seating any time you set the parking brake, with each click of the p-brake pedal, the bell crank/adjuster should click down the shoe one level until it hits a specific tension. If this auto-adjustment isn't happening, the gap from shoe to drum will be excessive, and braking will be sloppy/squishy/excessive pedal travel
  • Especially in the rust belt, the p-brake assemblage out back will be rusted, seized, or totally missing, which negates the ability for rears to auto-adjust, and will gradually see braking become worse and worse with time
  • Some people, during brake service, may not realize they *must* manually adjust the rears to get them in range, by clicking the star ring on the adjuster forward until there's a slight drag from shoe to drum; if the adjustment is too far out of whack, auto-adjust won't happen
  • Other factors we've seen, like using aftermarket parts (especially aftermarket spring kits) will also cause auto-adjust to fail
• The setting for the bell crank is absurdly tight tolerance, and you get shitty braking if not set correctly. The expected tolerance is less than the thickness of a good business card.
• The LSPV has several things that cause sloppy braking
  • If you've lifted the truck and didn't also relocate the LSPV mount upward to compensate, the amount of fluid/pressure exerted to the drums will diminsh, killing effectiveness of braking
  • The LSPV is at the highest point of the braking system in the rear, and is prone to holding air, which reduces function; a lot of people fail to bleed it (it has a bleeder), leading to excess pedal travel and mushy braking
  • If the LSPV has failed - which happens! - similar may be true
• Aftermarket parts/DOA parts --There's a ton of problems w/aftermarket parts, specifically with:
  • Warped drums and rotors right out of the box, causing pulsing while braking, drums are super common
  • DOA master cylinders right out of the box, or master cylinder pushrod is improperly set, max/min'd out totally, and the installer doesn't know to adjust it
  • Incorrect shape for the shoe bracket which shoes preventing auto-adjust
  • Incorrect spring shapes and/or tensions which prevent shoe articulation and adjustment
  • Bad or leaky boosters straight outta the box
• Bad bleeders/cracked bleeder lines/rusted brake lines with pinholes, the kinds of things that add air into the system, but usually there's a visual trail.

Those are the big ones I can think of to have in the back of your head while helping troubleshoot.

This could be something as stupidly simple as his auto-adjust feature wasn't working, or someone didn't know you *MUST* click-in your rear shoe adjuster to the point of dragging or the brakes would suck. Also true with the bellcrank adjustment.

 

And to that last point, the first step I would've taken here, before replacing the MC, would've been to confirm the rear brakes are adjusted properly, and OP is seeing slight drag with the rear wheels.

If not, that's the first symptom to resolve: Why were they not set properly, and is auto-adjust properly functioning?

 

Following @shifty` s point, how many clicks for your park brake to engage?

Low pedal can be due to excessive wheel cylinder travel from loose rear shoes.

 

thank you all i will be working on it tonight