Brake pedal went to floor?

[wjchop]

Bought my 06 4R not that long ago, bought it with some known issues as I got it for a killer price. One of those issues was shaking while braking, which I did a little research and figured even replacing all components Calipers, rotors, pads, etc would be $500ish front and back. I was going to run to the store today, which requires highway driving, I had no issues backing out of the drive or slowing down at the corner. I come to the stop sign push on the brake and there was very little braking, as I get closer I slap it in Neutral and start pumping the brakes, all the sudden RPMs kick up to 1,700, 4R leaps forward, then RPMs go back down and pumping must have done something as I got it to stop. Ended up taking it back home and taking the wife's suv.

After I got back I did some interwebs searching, it appears this is kind of a common issue, but almost everyone says they got alarms and lights going off before it happened. I got nothing. What I have found said check the Brake motor under the master cylinder and the accumulator, and since I already had the shaking issue further reading on the new issue brought to light the Toyota brake system flaw and it appears many people are putting Tundra Calipers an rotors on to fully solve the shakes. They don't really say what year Tundra, should it be same year as the 4R.

Has anyone done this and have knowledge to share, anyone else experience the brake "failure" issue I did, ultimately what was your fix?

 

[gaber6]

Glad you stopped in time.

No need to pump brakes on new cars.

However.

New rotors, calipers and pads are in store for you it seems. Also shocks and struts help keep the tires on the ground.

That MAY have made the pulsing more sensitive to activating the already sensitive abs system on these suvs.

If you hit sand or gravel as approaching a stop and the suspension moves, the abs kicks in for a few seconds with scary brake feel.

I did have ASE training in brake technology back before I decided to not be a mechanic.

 

[kc15842]

Shaking while braking in most cases is warped rotors. How many miles on the truck and brakes?
Depending on how easily the pistons retract I may not touch the calipers.

I suggest turning the front rotors and replacing the front pads. Do a break in on the new pads and see how it now stops. Keep it simple and do the front first to se if it takes care of the shaking. If the rears are worn then do the same on the rear.

 

[wjchop]

Shaking while braking in most cases is warped rotors. How many miles on the truck and brakes?
Depending on how easily the pistons retract I may not touch the calipers.

I suggest turning the front rotors and replacing the front pads. Do a break in on the new pads and see how it now stops. Keep it simple and do the front first to se if it takes care of the shaking. If the rears are worn then do the same on the rear.

It is right at 150k, my guess is these are the original rotors, but I haven't pulled the wheels off yet to look. Who knows on the pads, but yes I am just going to replace them regardless that way I know what is on there going forward.

As far as the shocks and struts, I plan to do a 3" lift and will just buy a kit that has shocks, struts and springs in it to replace everything. May replace UCAs too, depending how they look.

This is going to be my camping/lake/fishing rig, don't need anything fancy, just functional and looking cool isn't ever a bad thing either.

 

[MikeinNH67]

Well that's pretty scary, glad all is well. The only time I've seen this on any car was because of a blown brake line. Keep us posted.

 

[wjchop]

OK, well I changed pads, rotors and calipers. Rotors were extremely warped and a couple pistons on the calipers were sticking, so replaced everything. I have bleed these things three times now, and when driving the pedal still goes nearly to the floor before the breaks start slowing the 4R down. They work, but its driving me crazy I have to push the pedal so far down. Is there some kind of an adjustment on these things I don't know about?

 

[azgold]

I have a 2006 4runner V6 with 223 K miles on it and if your pedal went to the floor it has nothing to do with pads, rotors etc.....
Either your hydraulic booster assembly was serviced and not bled properly, or there is an issue with the booster assembly itself. Pump, motor, accumulator.

These parts can be purchased , but make sure your diagnostic is correct because the parts are pricey if you buy OEM ( which is what you should do)

 

[Berty_K]

OK, well I changed pads, rotors and calipers. Rotors were extremely warped and a couple pistons on the calipers were sticking, so replaced everything. I have bleed these things three times now, and when driving the pedal still goes nearly to the floor before the breaks start slowing the 4R down. They work, but its driving me crazy I have to push the pedal so far down. Is there some kind of an adjustment on these things I don't know about?

FYI, 4Runner (and toyota brakes) are squishy in general. Lots of travel before they start engaging. Driving my wife's CRV is always a transition because of how sensitive her brakes are. Not saying you don't have a problem, but something to consider as you debug.

I went nuts trying to firm up my pedal feel (redid brakes a 2/3 times, bled them, and took it to a mechanic) before just accepting it.

If you Google around, you'll see lots of people share similar thoughts about their "squishy" toyota brake pedals.


Sent from my iPhone using Tapatalk

 

[toyoman25]

guess I got lucky with mine....don't have this issue

 

[MikeinNH67]

guess I got lucky with mine....don't have this issue

Mine doesn't seem very squishy either. At least not after it got new rotors/pads all around and calipers in the front. New brake lines too. Certainly not as hard a pedal as my FIL's CRV but less squishy than my wife's Odyssey.

 

[toyoman25]

Mine doesn't seem very squishy either. At least not after it got new rotors/pads all around and calipers in the front. New brake lines too. Certainly not as hard a pedal as my FIL's CRV but less squishy than my wife's Odyssey.

Well it's a Honda After all lol

 

[MikeinNH67]

Ha, I've owned many Hondas, this is the only one that is like this but it seems to be common/normal on that generation Odyssey. It still stops very quickly for a van. Goes quickly too.

 

[Drcoffee]

Its time to replace the flex brake hoses. Two things can happen with them. Either they corrode and close down or get weak and expand under braking. Also, if Im not mistaken, if the pedal goes to the floor, you either have air in the line or the Master cyl has failed. I would start there.