2018 Tacoma Master Cylinder help please

Hello All,

I have a 2018 Tacoma Sport that I bought new in 2018 and just turned 36k miles.

Start of problem>>>6 months after buying it my brake pedal went soft. I would pull up to stop signs and sometimes the brake woild sink half to the floor and either continue rolling or make a hard downshift. Then the recall came out for the master cylinder. I took it to a dealer in NC to complete the recall. The brakes were perfect for exactly 1 week. Then they went back to nearly the same.

Dealer response>>>All Tacomas have a softer than normal brake pedal and they "re-bled" the system. The pedal was hard for about a day. I am a mechanic and I know they are not suppose to be like this. I argued with them several times to no avail. Their response, "recall is complete and nothing wrong with the truck"

I drove this thing back and forth to work having to start slowing down 1/8 mile in advance of every stop not knowing brakes going to fail knowing they sold me a lemon.

Here it is:
-The brake reservoir loses fluid with no leaks anywhere on the vehicle which tells me it is going into the booster (not sure why the geniuses at Toyota can't figure this out)
- When you hold the brake you can hear excessive rattling. Getting worse as time goes on which tells me the booster is going
- Called Toyota and asked them to fix it response is "No, one time replacement on recall and you are out of warranty" even though there is previous history and documentation
-Looked for others with same problem to find a solution as I do not want to put the same garbage master cylinder in it and cause the issue again
-Also I would like Toyota to take ownership of this in someway whether they pay for it or expose them for faulty parts/repairs because I bought it on the premise I was getting a Toyota not a Ford

My questions:
Has anyone had the same issue with the Master Cylinder (and now likely booster)? What did you do to fix it? What is the best solution for our Tacos to ensure this issue never occurs again? I do not want to put OEM parts known to be defective back in if I can avoid it

Thanks all for any help!!!

 

I would get one from a newer truck from car-part.com for $100 and be done with it. You can definitely take it to another dealer and have them diagnose a bad booster but then you will be stuck paying for it and then begging corporate to reimburse you the $1500 replacement bill on a part that had a warranty expire 4 years ago. Just make sure you get a SR/SR5/Sport/Limited booster and bleed it well.

 

Thanks for the response!

I am not looking to put a used part in it. I will buy new parts. I was looking to see if someone made a mod and had success with interchanging parts or if there is a modification out there. I know Tacomabeast has a changeover to Sequoia master cylinder for rear disk conversion but those masters have the same issue so it defeats the purpose. It is almost too bad one of the machinist haven't made a conversion plate and spindle kit to put a whole different master on them other than another faulty Toyota part

 

Happy Friday


Have a trustworthy independent Toyota shop diagnose the problem. Tell them the pedal goes soft.
Do not tell them what parts you think are bad, let them find the problem and tell you what needs to be done.

 

Sounds like something that should have been taken care of 6.5 years ago while it was still under warranty.

 

Been there done that. Over 10 times with the same response. See original post. At this point it is $100 for each diagnosis. I can spend that money to fix it the way Toyota should have in the first place which is replace it with a quality part. Not the same defective part with the same issues. They did that just to push people out of warranty. I have fighting these people for 6.5 years and get no where. Now I take matters into my own hands as us mechanics with business degrees and legal backgrounds do I will expose them once i take it apart on video. All I am asking from the group is options out there for replacing it with a reliable part which is clearly not a Toyota product that is defective. Thanks

 

Then go install your parts sans proper diagnosis and come back to tell us what/where the failure was when you are done throwing parts at your Tacoma.
You said the master and the booster is bad.
Sorry to hear that you have a shitty dealership, that fkn sucks.
Go, do it.
Autozone, O'Reilly, Napa, Willwood, take your pick ETC

 

"Sans proper diagnosis" ??? Clearly you have no idea what you are talking about. A dealer is NOT required to make a proper diagnosis. A knowledgeable mechanic can do that which clearly you are not. This conversation is clearly beyond your scope. As stated in the original post there is no fluid leaking anywhere on the vehicle this includes each brake cylinder, all the lines, on or around both master cylinder/brake booster yet it loses fluid this means the ONLY place the fluid can go is the seal between the master cylinder and brake booster filling the booster internally which is the original manufacturer defect thus the recall. THAT is a proper diagnosis. Now I could crack each line and pressure test them, bench check the master and waste 4-6 hours of my time but any mechanic with knowledge knows as soon as I split the master and booster I will find all my fluid inside that booster. I DO NOT need a dealer for that. I posted a little youtube of a Tundra with the same problem for mechanically inclined. If you love your dealer so much go give them a hug and kiss tomorrow but don't come on here an insult or berate me. I asked for help interchanging parts if you can't offer that help then don't respond. Now... Good day!

https://youtu.be/V1Q83GDmplY?feature=shared

 

What's the constant? Nice projection.

 

My 2011 had a "soft petal" fell to it from new. Stopped fine still does with 150,+ miles on it.

 

There are hundreds of thousands of good master cylinders/boosters running all over the planet. You got two bad ones. That’s pretty damn shitty luck. Me, personally, I would trust a used low mile later model (2023 if you can) OEM part over a new/reman OE or aftermarket part. The recall/TSB doesn’t cover all years if I’m reading it correctly so I would deduce that Toyota did something between then and now to rectify the issue.

I agree with your diagnosis of a bad seal in the MC. You did everything right by reporting it to Toyota over and over. Your next step is to call corporate and open a claim. It may get you nowhere but it may get you another free MC/booster in good faith and it may never fail in your lifetime. Or they put one on and it fails in a week.