Normal brakes are possible!

So a long (and basic) post coming, but thought I would share my personal experience with brake improvement and hopefully encourage others to achieve braking nirvana...

I bought the truck three-ish years ago and one of the callouts from the seller (also a good friend of mine) was that the brakes are unusual but "the best they can get and they're all like that". So I took it at face value, and my understanding was mostly supported by the frequent brake posts both here and other places, so assumed the brakes were "normal". So I lived with it, knowing that the brakes worked but really didn't engage (like I thought they should) until towards the end of the pedal travel.

Fast forward three years (to present time) and all was fine until I almost rear-ended someone TWICE in the span of a week. Both times were fairly unusual where the person started out from a light (with me following behind under acceleration) and then they changed their mind and slammed to a stop. Both times I also slammed on the brakes but both times I *barely* stopped short of contact. So at that point I decided to try to do something about it...

First step was to adjust the LPV to get more rear braking. That seemed to help as the brakes felt more "grabby", but still not what I would expect as normal.

Next I adjusted the rear brake shoes. This made a significant difference! I should have done this a long time ago but I trusted my friend and my assumptions (bad judgement on my part!).

So from there I bought a brake fluid tester and checked the fluid. Even though I had done a fluid drain and fill at the reservoir not long after purchase, the fluid tested "off the tester's capability" for water contamination (yikes!). So I did a vacuum bleed on the master and driver front caliper, but while trying to do the passenger front caliper the bleeder screw snapped off (ugh.). No amount of heat, impact, drilling, easy outs, tapping, or swearing would get the old screw out. New calipers were put on order...

After replacing both front calipers (also with new pads... not necessary but since I was in there) I did a *pressure* (not vacuum) bleed/full flush on the master cylinder, LPV, and all four wheels using Bosch DOT 5.1 fluid. During the pressure bleed I found that there had been some air in the lines that the vacuum bleeder did not evacuate. I can only guess that the higher volume fluid flow using the pressure bleed forced out the additional tiny bubbles of air. I found the most air in the lines at the rear brakes, but there were also some very small bubbles at the master.

The difference now is night and day... I would compare the brakes to any of my other vehicles in that the pedal feel is now "normal", and if I hadn't known of the common concerns with Tundra brakes I would never consider them as weak or abnormal.

So I share the saga to let you know that better brakes are indeed possible. Just go through each part of the brake system methodically to ensure that each area is functioning as it should.

For reference here are the parts I used:
Brake fluid tester:
https://www.amazon.com/dp/B08NH6FLXL
Brake fluid:
https://www.amazon.com/dp/B07338GQM8
Pressure bleeder, but modified to work with compressed air (swapped out the connector fitting to a standard air hose fitting, and used an inline valve/regulator/gauge contraption to control and monitor air pressure to 15psi maximum, and switch air flow on and off during bleeding):
https://www.amazon.com/dp/B0CPL15QLS

Good luck, you can do it!

 

Thanks for this post. You've given me hope that my brake situation can be improved. Wish you had posted a couple of weeks ago before I bought the air powered HF vacuum bleeder (same price). The vacuum bleeder kind of works, but I don't think it develops enough vacuum to properly flush all bubbles thru the rear brake lines and all the components between master cylinder and wheel cylinders.

I'm gonna buy one of these and give it a try. What did you use to pressurize it? (might be able to use my air compressor, using my spray gun regulator and gage to adjust/regulate it to 15psi max.)

 

I probably should have posted more detail on that in my original post... I use one of my compressors as the pressure source, and set the pressure as close to 15psi as I can tell from the regulator gauge.

To be doubly safe (to prevent over pressurization), I have a leak down tester that has a much better pressure gauge and regulator that I put at the end of the hose with me where I can set and monitor the pressure at 15psi (so I really have two gauges and regulators in series... I *REALLY* don't want to over pressurize the brake system). I also put a valve in line to allow me to turn the pressure on and off as I open and close the bleed screw and refill the master reservoir.

From the leak down tester and valve I run a second air hose to the bleeder cap and reservoir. I use the same hose/fluid collector from my vacuum bleeder and just make sure to refill the reservoir after every container full of fluid that is collected. It's basically:

Compressor --> Hose (to wheel I'm working on) --> Valve/Leak Down Tester --> Hose (to reservoir) --> Bleeder Cap/reservoir

If it would help I can try to take pictures and post later this evening.

Here's a list of the additional parts:

Leak down tester - I actually made my own from individual parts, but it's similar to something like this:
https://www.amazon.com/TU-21Cylinder-Automotive-Compression-Leakage-Motorcycles/dp/B0CDVZ42XC/?th=1

Inline valve: Attached to the leak down tester:
https://www.amazon.com/dp/B078W1L7GL

 

Using an air compressor, don't you worry about putting air into the lines containing a hygroscopic fluid? I can understand if you have a water separator on your setup, but I don't think most people do unless they're welding/plasma or auto body.

 

If you don't want to DIY a pressure bleeder, a Speedibleed is nice, compact and relatively affordable bleeder a few members on here use and recommend (me included).
https://speedibleed.com/product/k800b-toyota-lexus-brake-bleeder-kit/

 

I do have an inline drier, but I don't think it should be significant since it's only 15psi and only contacts/applies to the surface area of the fluid in the reservoir. The air doesn't go into the lines, only the reservoir (assuming you don't let the reservoir run dry... haha).

 

I agree, a dedicated pressure bleeder (Motiv is also popular) is probably the best way to go. I just used what I had on hand. My intent was to share the impact of pressure bleeding (by whatever device/method used).

 

What I’m wondering is if you bought this knowingly that you should have checked your major components, why did you just not do a bleed to avoid these issues?

If brakes aren’t working as they should and they feel “soft” wouldn’t your first instinct be to bleed the brakes to get a more firm feel?

 

Yep, I already admitted to that mistake. My bad!

 

Man, if you only knew the brake systems on these 1st gens and all the little weird idiosyncracies with them.

Maybe be hapy you have a 2021. There are entire threads dedicated to getting the brakes on these trucks back in whack. It's probably one of the (if not THE) biggest complaint on 1st gens.

 

Lol I love my ‘21. But wouldn’t the concept be the same to bleed brakes to increase firmness starting from from Passenger Rear then Driver Rear, then Passenger Front, then Driver Front?

 

Yes, but you'd add bleeding the LSPV in between your 1st and 2nd step.

Thing is, there's a lot of weirdness with the 1st gens. Like, if the LSPV isn't adjusted properly, brakes are spongy.

Or, if the p-brake isn't setup properly after doing any rear brake service (you have less than 1mm leeway on adjustment), brakes are spongy.

Or, if you do old-school bleeding, and push the pedal too hard to the floor while bleeding, you can blow out seals in the MC/booster, brakes are spongy.

Aftarmarket star adjusters tend to fit poorly and not seat properly, or jump and get mis-seated, brakes are spongy.

Get a single air bubble stuck at the LSPV, brakes are spongy.

I'd go on, but you get the idea. There's a valid reason @Teutonics missed it. There's sooooo much stuff that can go awry. More often than not, it's not a bleeding issue (at least in our 1st gen hivemind experience)

But hey, at least the engines don't blow up

 

Lol!! That’s not my generation of Tundra.

 

I’m jabbing at the 2022-2023 owners