Soft brake pedal questions

[Leksikon]

I've had my 97 Limited since around 99-2000 and for the first few years it was all roses, but sometime around moving to Arizona in 2004 I noticed that the brake pedal felt a squishy. The truck still stops fine when pushed, but it doesn't feel like it once did. When I first noticed the issue I took it the dealership in AZ and they checked the master cylinder (my first thought) as well as the lines and bled the system and couldn't figure out what was wrong but did agree that it didn't feel quite right, although they assured me at the time that the master cylinder was fine.

At the time I was living in an apartment and had no hope of dealing with it myself but now that I've gotten a house with a garage that I often kick my wife's car out of for months at a time while dealing with my other projects, I'm wondering if anyone's had similar problems and may be able to give me a starting point for getting better pressure on the brakes. I still do hope that the dealership was correct in stating that the master cylinder was good, but only because I'm hoping it's something simple that we hadn't thought of.

Posting this now because I'm about to replace the front pads/rotors (routine maintenance) and if someone's got any ideas about what else I should be looking at while it's all apart I'd appreciate the input.

I did search around for brake problems and do plan to do the 02+ Tundra calipers when it's time for the next set of pads, but I don't think that will help my current pedal problem (correct me if I'm wrong) and already had the replacement parts waiting.

 

[Leksikon]

I hate bumping my own threads, sorry to do so, but had another thought that I couldn't find much info on:

Is there any easy way to test your brake master cylinder at home? Never thought of trying to verify the dealership's info but it's coming apart tomorrow morning so figured I'd ask.

Thanks in advance

 

[nevada]

I hate bumping my own threads, sorry to do so, but had another thought that I couldn't find much info on:

Is there any easy way to test your brake master cylinder at home? Never thought of trying to verify the dealership's info but it's coming apart tomorrow morning so figured I'd ask.

Thanks in advance

with the engine off, press the pedal.
use steady pressure, and just hold it there for 60 seconds.

if the pedal drops slowly, the mc is bad. if its stays solid, its good.

this is a very simple test, and there have been times that a bad MC can still pass. BUT, for sure if it drops, its bad.
also, if its been YEARS, and it hasnt gotten worse, or completely gone out, i doubt the MC is bad.
they dont STAY that way forever. they'll get worse fairly quickly.

als, does that rig have rear drum, or disc brakes?
if drum, they could be worn, or out of adjustment.
often times a low pedal, is mistaken as a soft pedal.

 

[Leksikon]

It's got rear drums and I'm sure that they need to replaced (now) but they have been replaced since I first noticed the issue. I'll have to do some research on drums, it's been a while. What do you mean by 'out of adjustment'? I'm going back to high school era here and haven't cracked these open myself... am I remembering right that there's a small gear in the middle of the drum that applies pressure outward / inward to change how close the pads are to the drum?

Guessing here, I haven't touched drums in well over a decade and my memory isn't always that hot.

 

[CanadianTRD]

What do you mean by 'out of adjustment'?

Our drums are self-adjusting.

When you replace the shoes, back off the adjustment screw manually all the way then install the drum;

Pull the parking brake lever all the way up until a clicking sound can no longer be heard. [page BR-31, Vol. II, '99 Toyota 4Runner FSM]"

DONE

here's a helpful link

http://www.google.ca/url?sa=t&rct=j&q=%20site%3Ayotatech.com%204runner%20drum%20brakes&source=web&cd=10&ved=0CHwQFjAJ&url=http%3A%2F%2Fwww.yotatech.com%2Fattachments%2Ff2%2F66038d1167969127-rear-tire-locking-up-4runner-rear-brake-installation.pdf&ei=NA72T_-tHMHVqgHcxpCLCQ&usg=AFQjCNHWBbIKyK90pPe37hBCuYuMIsdKjw

Don't forget to tighten up your E-Brake in your center console before you start this whole process!

 

[CanadianTRD]

The tool they use in the FSM to measure Internal Dimensions of your brake drums, compared to the External Dimensions of your brake shoes (outside of one to the outside of the other) is a:

You can see the forks going up for ID, and the forks going down for ED.

 

[nevada]

out of adjustment, meaning not close to the drum. which requires more pedal travel for the brakes to hit the drum, and actually start working.

how far does your Ebrake pull? a long ways? when the ebrake is applied, does the brake pedal feel any better?

and, self adjusting in name only. most of the time that feature doesnt work.

just normal braking should adjust it.
we've found, that at best, if the "self adjuster" prevents the adjustment from backing off, we're lucky.

 

[CanadianTRD]

If you are worried about the self-adjusting mechanism...

With the drums off, rotate the hub.

You should be increasing the adjustment screw until you just feel some resistance. At that point they are close enough to let the parking brake and brake pedal take care of the rest.

(I don't have the 4runner wrenching experience most other members do...but generally speaking this technology is universal)

 

[nevada]

If you are worried about the self-adjusting mechanism...

With the drums off, rotate the hub.

You should be increasing the adjustment screw until you just feel some resistance. At that point they are close enough to let the parking brake and brake pedal take care of the rest.

(I don't have the 4runner wrenching experience most other members do...but generally speaking this technology is universal)

the drum needs to be on, atleast for when checking.

its best to leave the tire on aswell, and adjust from the inside of the backing plate.


also, IF you decide to pull the drums, do NOT touch the brake pedal. this can push the wheel cylinders out too far, and blow the cups out. at best, its a mess, and you have to bleed the system. at worse, you'll need to replace the wheel cylinders.

and, yes that info is pretty universal for drum brakes.

 

[Leksikon]

Glad I asked before I took anything apart. Thank you all for the info provided so far. When I sober up a bit in the morning I'll re-read all of this and check back when I get into it.

To answer the most basic question I can focus on at the moment, the E-brake pull feels solid, it engages at what I would consider a good height and doesn't feel weak or seem to have any abnormal amount of travel, it was adjusted when the rear drum pads were last replaced, and although that's been quite a while now it still feels pretty close to where it was then.

 

[jason in tn]

my own expriance has been the outo adjust on toyotas do not do enough no matter how much you use the e-brake the shoes need adjusted up on a regular basis, I thought after freeing up my e-brake and pulling the handle up once in awhile would be enough untill I smoked the front pads on a long down hill under hard brakeing.

 

[nevada]

my own expriance has been the outo adjust on toyotas do not do enough no matter how much you use the e-brake the shoes need adjusted up on a regular basis, I thought after freeing up my e-brake and pulling the handle up once in awhile would be enough untill I smoked the front pads on a long down hill under hard brakeing.

pretty much toyota, or otherwise. like i said, they are auto-adjusters by name only.

 

[S@nt0s]

with the engine off, press the pedal.
use steady pressure, and just hold it there for 60 seconds.

if the pedal drops slowly, the mc is bad. if its stays solid, its good.

this is a very simple test, and there have been times that a bad MC can still pass. BUT, for sure if it drops, its bad.
also, if its been YEARS, and it hasnt gotten worse, or completely gone out, i doubt the MC is bad.
they dont STAY that way forever. they'll get worse fairly quickly.

als, does that rig have rear drum, or disc brakes?
if drum, they could be worn, or out of adjustment.
often times a low pedal, is mistaken as a soft pedal.

i have the same issue as the OP my Ebrake engages fine with a few clicks and with engine off the pedal is solid and higher but with the motor running it gets soft and goes all the way down.

it stops fine but you have to go all the way down. Ive suspected my booster, perhaps we both have the same problem

 

[stever1000]

i have the same issue as the OP my Ebrake engages fine with a few clicks and with engine off the pedal is solid and higher but with the motor running it gets soft and goes all the way down.

it stops fine but you have to go all the way down. Ive suspected my booster, perhaps we both have the same problem

Did you solve your problem? I think I have something similar

 

[octanejunkie]

Did you solve your problem? I think I have something similar

Necro bump :doh: