Brakes not working Properly

I have a 2000 SR5 with 374,000 miles on it. I am having trouble with my braking system. It all started when i went to change my back drum brakes. After changing them i never could get a good pedal. I then went and changed both back wheel cylinders and both front calibers. While changing one of the calibers i broke a line and had to replace it as well. This still didn't fix the issues so i changed my master cylinder and bleed the whole system several times. I still have the same issue and needing help as to where i need to go next.

 

You said you bled the system. It sounds like to me you have air in your lines. Did you just do a run-of-the-mill bleed, or powerbleed? I've always heard it's virtually impossible to bleed by yourself without using a powerbleed kit to put constant psi on the MC reservoir.

 

Have the rear brakes been adjusted properly?

 

Did you bleed the LSPV (load sensing brake proportioning valve)? If you've ever accidentally introduced air into the rear lines, it won't matter how many times you bleed it at the brakes, it will still need to be bled at the LSPV. Look along the top side of the differential where the rear brake lines meet and you'll see the bleeder.

 

This. Need to know what all was replaced in the rears. If not adjusted properly they will seriously mess up pedal feel.

 

No i just did a normal bleed

 

i think so but i will have to double check a see.

 

i will try this next and see what the out come is...

 

I replaced all component parts from wheel cylinders to hardwear and shoes.

 

Yea if you've never done this, this is going to be the issue without a doubt. The proportioning valve measures the distance between the rear axle and bed and then adds more rear braking bias when that distance is reduced because weight has been added to the bed. Having air in that valve is effectively like having air in the lines going to both rear brakes. I experienced this problem this summer after breaking a rear brake line. I bled at the LSPV using a tube into a water bottle while someone pumped the brake pedal. Easy fix.

 

Let us know if bleeding the prop valve solves it. A lot of us have struggled with our rear brakes since they are getting so old at this point.

To make sure the drums are dialed in, jack up the rear axle so both tires are slightly off the ground. With the truck in neutral you should be able to hear the shoes just lightly drag the drums as you spin the tires. If they aren't you can manually adjust through the peep hole with a flathead. In theory, they should self adjust, especially if you just replaced the springs and self adjuster. That's not always the case in reality though. I'm actually hoping to replace all those parts on my truck soon.

If you search on here, people have posted those pages from the field service manual on how to adjust the rear drums.

 

I replaced both wheel cylinders so it was like i broke both rear brake lines.... I will try this and let you know if it works.

 

Does your parking brake work? If not, it's a good sign the rears aren't adjusted.

 

cheack your equalizer arm and make sure its not seized it located on the center of rear axle and the parking brake cord attaches to it i saw this somewhere soory no pics maybe someone has one they seize up from rust and some bushing go bad their and its a over looked problem for pb adjust

 

I did... Twice

 

Well gentlemen... the bleeding of the Prop valve did not solve the problem... didn't get a chance to check the adjustment of the back brakes yet, this is my next step. There may have been a chance of air getting back in my master cylinder while bleeding the system so i am going to bleed the whole system again starting with the master cylinder and then the wheels / Prop valve. On a other note i did brake a line on my left front caliber while replacing it so i am going to look at that again as well. I am still open to any help.

 

good idea and do you have an order that you bleed the calibers.? saw it mentioned somewhere it very specific and don’t woory many here have seemed to make this bleeding mistake at least 6-7 people just from reading all these posts these past few weeks. maybe someone will know.

 

I watched a video that said to start with the furthest from the master cylinder and work your way in from there. If anyone know the correct order for a 2000 tundra 4x4 access cab please let me know.

 

It didn't do dick for me either. A lot of people focus on the Prop Valve for some reason. I've been chasing a mushy brake pedal for 14 months now.

What brand master cylinder did you go with?

 

Here is what i got.... thinking i might have to go with a OEM if this round of bleeding don't work. I don't have so much a mushy pedal as to a pedal that just goes to the floor everytime it is pushed, but once I pump it a few times it is a sold pedal. During the bleeding process i get a sold pedal as well...

 

Same here. I pump the pedal once and the next time I push it's firm. You can look but I think Toyota discontinued the master cylinder.

Another thing to try, does your Tundra have ABS? If so, find some gravel and lock up the brakes several times so that ABS engages. Then go home and immediately bleed the brakes again. The idea is that air can get trapped in that ABS module and you need to burp it. This didn't work that well for me but it's worked for a few other members.

 

my 2000 tunny had not abs unsure but that feature did not come out until 2001??

might be brake lines swelling if they are the old rubber oem type swelling from old age

 

My 2000 has 4 wheel ABS. They key to all the brake woes are the rear brakes. The mushy pedal is the rears not engaging early enough. The system is "balanced" in that they all have to work together. If the pressure never builds in the rear, it won't pressurize the fronts. If you get the rears dialed in, it will make the whole system work better. Mushy or soft is likely the rears out of adjustment. Brakes that feel like they wanna go to the floor is likely air in the lines. The rears should drag slightly when spinning the wheel. The self adjusters are trash on these. There's even an improved version of the adjuster star wheel out there. I adjust my rears manually when doing my oil changes and tire rotations, and drive shaft U-joint and tie rod and ball joint lube checks. Keeps the brakes feeling relatively form, for a FGT. These will never feel like your Ford brakes.

 

It would help if you could expand on your comment "After changing them i never could get a good pedal" Is the pedal going to the floor? Are the brakes not engaging at all?

A lot of posters complain about our brake pedal feel. I know mine feels nothing like my previous F150 or Silverado. As others have said when in use on the highway a quick stab of the pedal, followed by actual braking pressure does improve the "feel" of the pedal.

 

This gen doesn't have a "solid" pedal - takes getting used to, which is good cuz most vehicles with that type of pedal feel lock up too easy. It should be smooth, progressive yet if you hammer it down, should nearly cause ABS to activate. Does yours do that?

 

I have owned this truck since 2003 and only the second owner. i am aware it doesn't have a super hard pedal but it has never went to the floor like this.

 

are you seeing bubbles while bleeding the brake fluid?

As stated before, make sure the rear brakes are adjusted properly. If the shoes have too far to travel, the pedal will not feel right. I have had this experience before with my 1st gen. If you can tighten them up too much, then bleed, it may make things easier. Just remember to loosen up when finished.

 

My suggestion is get a MityVac (or clone) and bleed the truck RR, LSPV, RL, FR, FL twice around. Air gets trapped in those ABS lines.

 

If you’re having to pump up your brakes, it indicates that the problem is air somewhere in your system. What’s the condition of your fluid? Have you tried completely draining all the old fluid and refilling with new fluid?

Also, as mentioned above, ABS modules tend to trap air and sometimes bad brake fluid. You can command the ABS to cycle and bleed these valves with a scan tool.

 

@Nobody6966 Like Dunk said, the double pump of the pedal before building good pressure is a symptom of air in the lines, so I don't think you have a faulty master, just air trapped somewhere. Mine behaved exactly the same before I bled the LSPV.

The order for bleeding is supposed to begin at the farthest point from the master and the move to the closest point, so RR, RL, FR, FL. Originally I assumed that the LSPV should be in the middle of that sequence somewhere, but my Hanes manual shows it as being the next step after bleeding all the brake bleeders first, for whatever reason.

Since bleeding it yourself doesn't seem to be doing the trick, if this were my truck, my next step would be having a professional bleed the system for me. You may have more confidence than me and be willing to continue trying things, but that is probably what I would do.