@ChaseTruck has a good point I may have missed earlier.
Please define "jam pedal super hard to stop".
When the booster goes, you will practically have to stand on the brake pedal to stop.
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Please define "jam pedal super hard to stop".
When the booster goes, you will practically have to stand on the brake pedal to stop.
- Thread starter
- #22
I don’t think it’s the booster. I did the test from the shop manual and it checked out. Pulled the vacuum off to feel the difference and it was night and day.
Could however be an adjustment with booster.
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- #23
Booster is easy to test. You just pump
the pedal up whit the car off, keep your foot on it when you start the car. It should drop to the floor. If not, the booster has failed.
But it can fail intermittantly....
My booster passed all the tests listed above.
I'm old enough that I knew immediately that the problem really was the booster. I ran the tests because I thought there was a chance I wouldn't have to spend that much.....
Mine failed overnight, as in it was fine one day, the next I almost rear ended one of our other cars the next morning because the pedal was rock hard, then it would fade to the floor.
I replaced the booster with a new Toyota unit and the brakes were excellent. That was two years ago.
A few weeks ago I went through the rear axle and also did Toyota calipers, Power Stop rotors and pads, all new hoses and my brakes are excellent again. I also gained 2 mpg because one side was dragging.
I'm old enough that I knew immediately that the problem really was the booster. I ran the tests because I thought there was a chance I wouldn't have to spend that much.....
Mine failed overnight, as in it was fine one day, the next I almost rear ended one of our other cars the next morning because the pedal was rock hard, then it would fade to the floor.
I replaced the booster with a new Toyota unit and the brakes were excellent. That was two years ago.
A few weeks ago I went through the rear axle and also did Toyota calipers, Power Stop rotors and pads, all new hoses and my brakes are excellent again. I also gained 2 mpg because one side was dragging.
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- #26
I guess so. Almost like it’s partly working.
It seems to behave like a normal car till you have to stop fast. When I disconnect the booster it feels odd 100% of the time. So it’s doing something.
That's the clue right there. Sometimes it feels like when you purposly disconnect the vaccum, mostly if feels normal.
Its a bad booster. Just a matter of time till it fails completely.
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- Thread starter
- #28
It’s not “normal”. I would not say that. You have to press the pedal pretty hard. But I am wondering if there is a leak. Working under low pressure but not higher pressure (hard braking).
It's the booster.
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- #30
Any advice on a generic booster? The one in there looks generic.
I am worried about not using
OEM. But Can’t afford one now.
I saw some videos where the shaft length were different and I don’t have an OEM one to compare it to.
Thanks again for all the help.
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- #32
I am leaning towards the booster more now. I just think will all that bleeding, I would have felt some difference and not much improvement at all.
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The booster made by Seiken is the one you want though.
You may or may not have to adjust the stem, its not a big deal.
And if you're thinking of buying from PartsGeek because of the price, just don't. Trust me.
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- #34
Well I did order from parts geek but got the same one thats suppose to be OEM. I was worried I could not return it to some of these other companies if it did not fix the problem. I am on a budget with this repair.
| Brand | Seiken |
| SKU | W0133-1740427 |
Good luck with Parts Geek. I wounldn't piss on them to put them out.
Malleus
Far west of Siegen
@lcrva
The OEM booster has been delisted by Toyota. Currently, you can't buy one from them, unless it's from the dealer stock in the US (for a lot of cash).
There are still a few Toyota brake boosters in private warehouse stock in Japan; they're listed on Ebay. (I have no relationship with these guys; I only mention them because I bought from them - there are other Japanese sellers as well) They are currently advertised at about $385, less shipping; I have one on the way right now. They aren't as expensive as the dealer models, but they aren't cheap either. There are also Australian sources; look for them and you'll find them.
I know it's hard to spend money you don't have, but for the extra price (Seiken aftermarket boosters are running $300 now) and the peace of mind knowing you'll have a genuine part, I bought the OEM booster, when mine failed. In my case, the decision was easy, I knew the booster had failed.
From personal experience, throwing parts at a brake problem is just expensive. Not smart, just expensive. Like any hydraulic system, you cannot troubleshoot brake system problems by replacing parts. You may get lucky, but you'll definitely spend money doing it. You really need pressure and flow gauges to do the job, and they aren't cheap, considering you'll probably never use the tools again.
There's no harm in replacing the hoses, but there's also no guarantee that doing so will solve your problem(s). Also, please bear in mind that no one can troubleshoot a brake problem over the phone. The best any one can do is provide advice that you then have to use to find and resolve your problem.
I can't see your truck, but from what you've described, if it was me, I'd spend as much time cleaning and replacing wear parts (rebuilding calipers if necessary), before I spent money on expensive parts. Again, that's just me and my time spent on my trucks is as valuable as I want it to be.
The OEM booster has been delisted by Toyota. Currently, you can't buy one from them, unless it's from the dealer stock in the US (for a lot of cash).
There are still a few Toyota brake boosters in private warehouse stock in Japan; they're listed on Ebay. (I have no relationship with these guys; I only mention them because I bought from them - there are other Japanese sellers as well) They are currently advertised at about $385, less shipping; I have one on the way right now. They aren't as expensive as the dealer models, but they aren't cheap either. There are also Australian sources; look for them and you'll find them.
I know it's hard to spend money you don't have, but for the extra price (Seiken aftermarket boosters are running $300 now) and the peace of mind knowing you'll have a genuine part, I bought the OEM booster, when mine failed. In my case, the decision was easy, I knew the booster had failed.
From personal experience, throwing parts at a brake problem is just expensive. Not smart, just expensive. Like any hydraulic system, you cannot troubleshoot brake system problems by replacing parts. You may get lucky, but you'll definitely spend money doing it. You really need pressure and flow gauges to do the job, and they aren't cheap, considering you'll probably never use the tools again.
There's no harm in replacing the hoses, but there's also no guarantee that doing so will solve your problem(s). Also, please bear in mind that no one can troubleshoot a brake problem over the phone. The best any one can do is provide advice that you then have to use to find and resolve your problem.
I can't see your truck, but from what you've described, if it was me, I'd spend as much time cleaning and replacing wear parts (rebuilding calipers if necessary), before I spent money on expensive parts. Again, that's just me and my time spent on my trucks is as valuable as I want it to be.
- Thread starter
- #38
I think it’s time for a real mechanic. I am out for free days to mess with it. I did try and reinstall the old master cylinder…. There was a noticeable improvement with how new MC so I am keeping that installed even if that not the issue.
Sorry to hear that.
Didn't realize you were going to change the MC also. That may have actually introduced a new problem.
Did you get the system properly bled? LSPV, RR, LR, RF, LF, LSPV with LSPV arm disconnected and pushed all the way up?
Did you get the two push rods properly adjusted between the MC to booster and the booster to pedal?
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- #40
I have everything bled. Did pretty much what you said but did not disconnect the LSPV. I will give that a try. Are there any videos online that show you how?
