stevennc

Basically I have a binding midway through depressing the brake pedal. It feels like a mechanical binding and it makes a noise that I believe is coming from the booster, or some portion of the pedal assembly attaching to the booster. Braking is fine before and after you push through the resistance. Sometimes it binds sometimes it doesnt and the binding can be harder or softer to push through.

The truck has 278,000 miles without a replacement of either the booster or master. If I do indeed have to replace one or the other, I believe I will just end up doing both.

Could it be a binding of just the pushrods or pedal assembly , or is there a portion I can grease that would make the binding go away?

stevennc

I picked up a master and booster from pick your part. Still haven't pulled the parts from my truck as I am waiting for rebuilt calipers to finish the job.

After looking at a master cylinder innards I was wondering if a worn seal on the master cause a binding in the braking?

RAD4Runner

I have a similar intermittent problem. I inspected the brake pedal mechanism and could not find anything that's causing the problem. My cousin who has some auto experience says it sounds like a booster issue. Did you eventually get the booster replaced? How complicated was it?
TIA

osv

there might be a nylon bushing around the shaft that the brake pedal arm rotates on, and the nylon is ground off, so it's metal-to-metal.

RAD4Runner

I did not notice that, OSV, but will double-check. Thanks!

Meanwhile, I'm starting to shop for a replacement booster. Toyota Parts Deal website lists PN 44610-35810 but it has been discontinued, so I'm looking for after-market.

Rock Auto lists a remanufactured A-1 CARDONE 532071 here,and says it uses 100% OEM parts. The price is right.
Oreilly has this (BrakeBest Brakes Brand)
Napa has its own (NAPA Brake Boosters Like) here.

Does anybody have any experience with any of the above?
Is there a Toyota OEM brake booster (say from a different vehicle/model/year) that would be compatible, instead of after-market?

Rock Auto Website:

osv

i think that there are basically three boosters in general use these days: small diameter dual stage, large diameter single stage(what you have i think), and large diameter dual stage(out of t100, what i'm running).

you should take this opportunity to consider a first-gen t100 brake booster: http://home.4x4wire.com/erik/4runner/brakes/

he had already upgraded the master cylinder, but i think that the t100 booster will bolt right in, even with the factory m/c that came on your truck... do some more research tho.

if you really want one of those original large diameter single-stage boosters, i have one in my garage you can take, $5.00, pick it up today in north county i also have a small diameter dual-stage booster, if you want that also.

RAD4Runner

Thanks OSV,
I'm pretty happy with my brake system, because I drive conservatively, so would prefer to keep it stock.
Thanks for the offer, too, but I wanna save on man-hours so I'd like to install a "new" part. BTW, which North County might you be in? I'm in Riverside County, So Cal.

osv

i thought that you were in san diego? it's a drive from riverside, so that won't work.

the large dual-stage m/c booster is stock on the t100, it's a very worthwhile upgrade, i got mine at a junkyard, it's been great, if it fails i have a cheap core trade-in on a rebuilt unit.

RAD4Runner

Oh, didn't know you're in SD. Yes, was in SD but staying in Riverside as I look for a steady job in SD

Will look into it.

8_9_runner

89 V6 4runner having same issue. Mechanic says its the booster. Have not fixed yet.

stevennc

used booster, new master other parts fixed it completely.