My 4Runner broke a brake line
Intermediate
Joined: Feb 2009
Posts: 454
Likes: 4
From: KY
I’m almost certain that if the brake system becomes disconnected at one corner, it’s unable to build pressure at the other three corners and therefore the car would lose all stopping power unless you were using the e-brake. All the fluid in the reservoir would just exit through the disconnected area until it was gone, right? Each brake doesn’t have its own reservoir so how could there still be pressure in the other three lines?
I have no idea about whether both lines were broke. Or something else. But I have fluid all over the one side of the frame near the steering column. I did see that there was something about dual lines. But I was also reading on a few 4Runner forums about the 4Runner losing brakes in multiple instances.
Brake fluid eats paint too, wipe it off any paint you don't want removed. This includes undercarriage that is anti-corrosion.
My 4Runner broke a brake line today. Total loss of braking. Vehicle simply would not stop, coasted for about 1/2 mile until I was going slow enough to put into park.
Happy I was not on the highway.
Happy nobody was on the road
Happy it was a quite Sunday on a side street
Happy it was not in a school zone
Happy I was not on the highway.
Happy nobody was on the road
Happy it was a quite Sunday on a side street
Happy it was not in a school zone
Thread Starter
Lexus Fanatic
Joined: Nov 2011
Posts: 35,381
Likes: 357
From: ON/NY
Nope. Went into neutral, then slow enough to drive. Didn’t really think about the downshift till after to be honest. Happened so fast. I was not driving at speed. It was just after I got in, start the vehicle, just started moving when I realized to no brakes. No on a downhill either.
Yikes, that is scary.
Glad you're safe.
I was going to ask what was the first sign until you posted this.
Has it been determined that it's the brake line or is it a bad master brake cylinder?
Glad you're safe.
Nope. Went into neutral, then slow enough to drive. Didn’t really think about the downshift till after to be honest. Happened so fast. I was not driving at speed. It was just after I got in, start the vehicle, just started moving when I realized to no brakes. No on a downhill either.
Has it been determined that it's the brake line or is it a bad master brake cylinder?
In 1978 I was in USMC boot camp, after graduation I was ready to drive home but as I approached my '71 Firebird Formula from behind I saw fluid on the pavement under my rear axle. When I looked underneath I saw brake fluid leaking from the rubber hose that connected to the hard brake lines that sent fluid to each rear brake.
Next I checked the master cylinder which had a separate reservoir for front or rear brake fluid. The rear reservoir was nearly empty & the front was full. I drove the car slowly to test the brakes. After a few stops the rear stopped braking. I drove the 436 miles home easily by allowing for increased stopping distance & braking with all 4 tires pointing straight ahead.
Next I checked the master cylinder which had a separate reservoir for front or rear brake fluid. The rear reservoir was nearly empty & the front was full. I drove the car slowly to test the brakes. After a few stops the rear stopped braking. I drove the 436 miles home easily by allowing for increased stopping distance & braking with all 4 tires pointing straight ahead.
The ELEPHANT in the room is being ignored.
How is it that the OP lost ALL Braking?
Dual braking systems went in all cars sold in USA, in the early1980s.
Breaking "a brake line" could not make the OP lose all braking power.
Dual system, 2 wheels (diagonally opposite) whould still have brakes if one brake line broke.
Did the OP, who forgot about emergency brake, have the power-brake booster go out, and think: NO BRAKES !!
Or did both lines manage to go out at once - Sounds improbable to me.
Where oh where are some of you people getting your information??
Parking/Emergency brake is mechanical, an acts on rear brakes only.
It's there for a reason, generally :
(a) Parking on hills, if you worry about your automatic transmission letting go, and
(b) Emergencies - if/as/when brakes fail, gives you at least some braking ability.
Will it make your car (or your head) spin .. I guess it could, but it should not.
/
How is it that the OP lost ALL Braking?
Dual braking systems went in all cars sold in USA, in the early1980s.
Breaking "a brake line" could not make the OP lose all braking power.
Dual system, 2 wheels (diagonally opposite) whould still have brakes if one brake line broke.
Did the OP, who forgot about emergency brake, have the power-brake booster go out, and think: NO BRAKES !!
Or did both lines manage to go out at once - Sounds improbable to me.
Where oh where are some of you people getting your information??
Parking/Emergency brake is mechanical, an acts on rear brakes only.
It's there for a reason, generally :
(a) Parking on hills, if you worry about your automatic transmission letting go, and
(b) Emergencies - if/as/when brakes fail, gives you at least some braking ability.
Will it make your car (or your head) spin .. I guess it could, but it should not.
/
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if a park/emergency brake is engaged with a 'ratcheted' hand brake handle or foot bedal, there's no way to moderate it. with the hand brake at least, you can usually hold the button pressed in and modulate how much braking you want, but yes, slamming the foot pedal park brake is a bad idea.
Thread Starter
Lexus Fanatic
Joined: Nov 2011
Posts: 35,381
Likes: 357
From: ON/NY
Yes. Perhaps I didn’t hear the buzzer. I had the radio on. And perhaps I did not see the dash light. This all occurred within 30 seconds of starting up my vehicle. Felt something was off as the transmission shifter was very easy to go into park, which the 4Runner started move while my foot was pushing down on he brake.
Thread Starter
Lexus Fanatic
Joined: Nov 2011
Posts: 35,381
Likes: 357
From: ON/NY
Not yet sure what what it was. Waiting to here back from the mechanic.
Thread Starter
Lexus Fanatic
Joined: Nov 2011
Posts: 35,381
Likes: 357
From: ON/NY
The mechanic today told me this happens more than you think which echos the tow operators comments.
Last edited by Toys4RJill; Jun 17, 2019 at 02:35 PM.
Lexus Fanatic
Joined: Oct 2003
Posts: 94,328
Likes: 236
From: Virginia/D.C. suburbs
Yep....I brought that possibility up earlier. That was my first reaction, too....especially if one does not regularly flush the underbody and wheel wells with a hose, whenever temperatures above freezing permit.