Brakes still squishy and unresponsive after flush/bleed

Ever since I can remember I've had poor braking. I checked the rear boots today which were fine, and I bled them again and the LSPV (which I never did before). Nothing has changed. My same-year 4runner does not have this issue, but it has the ABS module. What could be my problem?

I plan to upgrade to Tundra brakes eventually, but I don't want to be chasing the same issue then.

To clarify, I can brake safely, but I have to start braking sooner and brake much harder than should be normal to actually stop.

 

Rear drums adjusted properly? Rotors, drums, shoes and pads all clean and in good shape? No grease on friction surfaces?

How are you bleeding the brakes?

 

This is the way

 

Ya just checked rear adjustment, was fine, even a bit tight perhaps. Everything in shape and has life left, front pads are ceramic.

Isn't glaze normal? They look glazed on all my cars. I can post pics of mine if that'll help. Pads are fine. Shoes have never been replaced so no idea of quality. Front pads are the high tier you get from autozone.

Also no noises from any corner.
It's almost like there's not enough pressure or some kind of pressure drop as you press the pedal.

 

Your signature/avatar would suggest you're fairly experienced...nevertheless, would you care to share your bleed procedure? How does the pedal feel? Could the MC be bad? Booster?

 

Has the master been bled?

 

I suspect the brake flex lines might be the issue.

 

In an otherwise stock truck, there should be no need to do the tundra brakes. Stock is more than sufficient, assuming it's all properly functioning, that is... It's only when you end up with larger tires, or an overall heavier rig (all that overlander junk people carry around), or you tow a trailer that doesn't have brakes that the tundra brakes become important.

On pickup trucks, the rear brakes hardly contribute. I'd focus more on the front brakes, but of course make sure the rears are good to go too. Also look at your LSPV position. For example, if it's been lifted, and you didn't adjust the LSPV, now the truck thinks it's even lighter in the back, sending even less braking power back there.

Make sure pads and rotors are in good shape, and frankly, probably should just replace them anyway.

Also look at your rubber flex lines. Again, probably should just replace those anyway. The rubber ones brake down over time and can expand under pressure without seeing any outward signs of damage when just sitting there. Steel braided lines aren't that expensive and are easy to replace.

Another bleed will be needed of course, so make sure you are following the "standard" bleed procedure (search for it, there's a certain order which you should bleed each corner and the LSPV. I really like my Motiv power bleeder, btw...

I definitely felt a difference when I did my braided lines. Could just be in my head, but that's the story I'm sticking to, lol...

 

Have you read my mods?

Other than that, was wondering if stainless brakes lines would make the difference. I have no idea how much flex my rubber ones have, so I'll probably just do it when I do the Tundras. I did recently add the LSPV height-jacker (just a couple inches via scrap metal) and didn't notice much change. Hopefully braided makes the difference

 

Not sure how to do this.. kinda the direction I was getting at with this post

 

There’s a kit you get at the store with some hoses and fittings that fit on to the master. They make it possible to push the air out and suck in fluid. It’s pretty straightforward


Dorman 13911 Master Cylinder Bleeder Kit - 22 in. Hose, Clip, SAE and Metric Fittings

$11 Dorman 13911 Master Cylinder Bleeder Kit - 22 In. Hose, Clip, And Sae And Metric Fittings Universal Fit

https://www.amazon.com/dp/B001SG8ZC0

 

Experienced in certain areas, heh. I went and bought a little kit from autozone last night just to make sure I wasn't getting air sucked back in. I started with the res cap off, connected to rear passenger, opened valve, pushed pedal 3 times, verified no bubbles, then closed valve and moved to next. I went rear pass, rear diver, LSPV, front driver, front passenger (probably flipped those two but oh well).

 

So I watched the beginning of this: https://www.youtube.com/watch?v=tq6FcjrSrdg
But I don't understand how air doesn't immediately go back in through the threaded fittings when you take the hoses off. Tbf I really don't understand where the air is coming from in the first place.

 

Air comes from inside the mc and is pushed into the reservoir where it escapes. The hoses are submerged so no air gets pulled back in as the fluid cycles through the mc

 

bench bleeding the master cylinder is the preferred method but if you crack the lines where they attach and have a buddy slowly press the brake pedal AND there is air it will be apparent as there will be a spitting sound. I use rags and cover the line as it goes into the master cylinder to avoid as much of the mess as possible. In extreme cases where I just cant get a solid pedal I will buy a length of the appropriate fitting brake line cut the tube a few inches from the end and fold it over to seal it, install the lines then bleed the master and then test the pedal feel... it should be an instant rock hard pedal.

 

Do the calipers have a seized piston(s)?

 

There's no need to bleed the MC if you never let the fluid get down enough for it to get air in the first place.

I saw that you wrote you pressed the pedal after opening the bleeder valve. Have you tried bleeding with someone in the truck applying pressure? Probably a dumb question but we need to know. Lol

 

Nope I'm a one man army lol.

 

You can do the pole method, but sometimes the pole moves out of the way. Lol. Maybe a neighbor?