Squishy Brake Pedal

[LandCruiser]

Speaking of Transitioning.... Go from driving a 5 Speed Manual Honda Accord for 16 years and then get in any automatic and try to remember that the car you are driving doesn't have a clutch! My wife hates it when I reach for the clutch that isn't there and ultimately catch just enough of the break pedal to jerk everyone in the vehicle!

Back when we had an MT car, I used to kick the floorboard of every AT vehicle I used to get into at startup.

 

[fourrunner1]

my 2014 does it too, annoying.

 

[Stifler]

fluid flowing across a tuned orifice

Wait arent we talking about squishy brakes?

 

[sandcrawler]

Hi guys,

New to the forum, just got the 4runner trail and it's absolutely stupendous, I love the old school high low shifter. However, I noticed that after 400 miles of driving the brake pedal makes a squishy sound when depressed. I sprayed a little white lithium grease on what i think was the rod (its hard to get to) but it didn't help. Has anyone experienced anything like this? I know some people think it isn't a big deal but it drives me crazy. :uzi: Thanks in advance y'all

-Carlos "El Bandito"

my '06 did it... my '10 does it... recent vintage 4Runners do it—it's normal. console yourself by giving the manly-man transfer case lever a pull and enjoy your new rig.

 

[Sac State]

A deer jumped out in front of me while driving 35mph. The brakes locked up and kinda surprised me. The vehicle stopped, but I wasn't expecting such a forced stop.

I applied the brakes faster than normal, but I did not apply enough pressure to force a lock-up.

Now I know why.

 

[Jesserue]

Just had my 20k service done at the dealer. Funny thing is that my squishy brakes were very tight after the service. No idea why or what they did. Only service request I made was standard 20k stuff. Noticed it immediately upon pulling out of the dealership. Did not have to depress the pedal nearly as far as usual to engage. Unsquishyness stuck around for maybe 10 miles and then back to squishy.:noidea:

 

[Maui73]

My 2011 does it too. It was fine until about 9K miles, then the brake pedal travels further down and makes a squish/squirt 'sound'. Drove me nuts. I have 3 cars and when I go back to the 4runner, the deep pedal travel makes my heart jump sometimes on a mild emergency braking as I thought I didn't have any brakes. I think the "squishy" that people refer to is a sound, not a feeling. And again the pedal travel is deeper / more than most cars. We had the 2 previous 4runner generations and the brakes on those seem more in line with other cars. Anyways, I just want to mention that I have this issue too.

I'm kinda used to reminding myself that my 4 runner has deeper / more brake pedal travel so I don't get off guard on some mild emergency braking. Also, my co-worker heard that squirt/squish sound every time I braked, so i know it's not just me, plus some of you guys too hear it too.

I noticed too that when some auto-brake activation happens (clicking, pulsation, etc.), the issue tends to go away for few miles, then it comes back.

I hope somebody find a way to remedy this.

 

[MSinDC]

The other ones I've drove haven't done it either. Mine doesn't pulsate tho…can't lose em all i guess :high5:

You've called it a squish and a squeak, which are two different things. If it's squeaking I'd take it in and get them to check it out. If you're talking about a "squish", "whoosh", or "pffff" then I'd say that's normal.

I enjoyed typing that.

 

[chiz45]

Just wait until he walks into his garage a few hours after driving, and hears the whirring sound under the truck's rear...

 

[BobsTrail]

There is more in addition to the brake pedal sound. Mine is an old 2013 but I'll bet the others do it too:

About 5 hours after shutting it off you will hear a small motor sound from the rear and immediately after shutting it off it will make a gasping sound, like and old guy. It's all OK and not a problem. It's part of the fuel evap/emmissions system.

 

[Bino9905]

Engineer couldn't the tuned orifice be bypassed?
Block the flow to it somehow....stopping the sound and the ability for it to sense the panic brake?
This would still leave a fully functional brake system but just not this "nanny" brake feature.......

 

[SkidPalace]

Engineer couldn't the tuned orifice be bypassed?
Block the flow to it somehow....stopping the sound and the ability for it to sense the panic brake?
This would still leave a fully functional brake system but just not this "nanny" brake feature.......

Or maybe relocate the flowmeter to the engine compartment (or otherwise isolate it acoustically)?
Took a new '15 limited out for an extended test drive the weekend before last and the 'ol lady and I were asking each other what the hell that weird chirp was. Then I figured out it was happening with each brake pedal press. That truck had 6 miles on it so yes it happens from new.

 

[Randyman...]

I also noticed this during the first 2-3 months of ownership (from 7 miles on the ODO). The perception of the "Shhhh/swoosh" braking effect fades with time, but the "Panic Assist" feature still catches me off-guard sometimes (even after 68K miles and plenty of Panic Assist activations).

As 1E mentioned, the panic-assist is based off how quickly you depress the brake pedal, so even a "light but quick" pedal-press can sometimes trigger the assist when not really warranted. Can be disconcerting with unsuspecting passengers riding along, but at this point I can generally anticipate when it will be needlessly triggered.

 

[SkidPalace]

Can panic assist be disabled with techstream?

 

[M1911]

A deer jumped out in front of me while driving 35mph. The brakes locked up and kinda surprised me. The vehicle stopped, but I wasn't expecting such a forced stop.

I applied the brakes faster than normal, but I did not apply enough pressure to force a lock-up.

Now I know why.

That's exactly what brake assist is meant for. Mercedes Benz did a lot of research and found that in emergency situations most people weren't hitting the brakes hard enough. They hit the brake pedal fast, but didn't push hard enough, so they didn't get full braking force. They came up with brake assist to solve that -- if you push the brakes fast, but not hard, the brake system will interpret that as a desired panic stop and will apply extra braking beyond the force you are applying. Mercedes was first, but other manufacturers eventually followed.

 

[M1911]

Can panic assist be disabled with techstream?

I doubt it. It is a core safety feature.

 

[FrontRange4Runner]

Please for the love of God, don't attempt to "re-engineer" the breaking system. I never notice my squish sound anymore (though for the first 5k it drove me nucking futz). No one outside of the Toyota engineers knows the parameters of the system. Messing with it could lead to you damaging your self or worse, some one else. It's an annoying noise - your brain will tune it out just like every other annoying noise that you don't know you're hearing right now.

 

[Randyman...]

Can panic assist be disabled with techstream?

I doubt it. It is a core safety feature.

Please for the love of God, don't attempt to "re-engineer" the breaking system.

Indeed - Very unlikely, and agree with FR4R this is not an area for so-called end-user "improvements".

It would be nice if the depth threshold could be tweaked to prevent activation with lighter (but quick) taps. I guess Grandma is the least common denominator here (as far as Legal is concerned) :lookout:

 

[SkidPalace]

Please for the love of God, don't attempt to "re-engineer" the breaking system. I never notice my squish sound anymore (though for the first 5k it drove me nucking futz). No one outside of the Toyota engineers knows the parameters of the system. Messing with it could lead to you damaging your self or worse, some one else. It's an annoying noise - your brain will tune it out just like every other annoying noise that you don't know you're hearing right now.

I think there are two separate concerns here. The squishy, squeaky chirp annoyance, and the actual panic brake assist feature that causes said audible annoyance. I seem to have gone off topic by inquiring if the panic braking system can be disabled. My intention was not to suggest that the annoying noise would be stopped (I would highly doubt that it would) but to simply disable the nanny system completely. My thoughts are that it is a "dumb" passive safety feature that could cause panic on its own if not cause an outright rear-end collision. If this was tied to a true collision avoidance system with cameras and a brain, well that would be completely different and completely welcomed on my vehicle.

 

[1engineer]

I think there are two separate concerns here. The squishy, squeaky chirp annoyance, and the actual panic brake assist feature that causes said audible annoyance. I seem to have gone off topic by inquiring if the panic braking system can be disabled. My intention was not to suggest that the annoying noise would be stopped (I would highly doubt that it would) but to simply disable the nanny system completely. My thoughts are that it is a "dumb" passive safety feature that could cause panic on its own if not cause an outright rear-end collision. If this was tied to a true collision avoidance system with cameras and a brain, well that would be completely different and completely welcomed on my vehicle.

If you have ever used this feature then you would realize that the panic it will cause won't happen until you are stopped or almost stopped or driving away safely after almost hitting something. When in the middle of a panic braking situation with the 5th gen 4Runner it's not like you are thinking or have time to think "Hmmm, these brakes are slowing me down WAY faster and harder than normal. Let me let off the pressure a bit and see if I can just perform slowing down better than this braking system." Basically what happens is "OMYGOD a deer! hitthebrakesWHAM HOLYCRAP i'm STOPPED WTF how'd that happen?" This feels like it took nano seconds. You learn after a time to expect it, sorta, but it happens much faster than your brain comprehends it.

To disable this feature would be idiotic. Just my opinion of course.