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Old 21st March 2011, 15:15   #31
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Default Re: What to do in case of Brake Fail !!

The good news is, brakes rarely fail in modern cars. The bad news is, they still do (rarely)!

In the unfortunate event that your brakes fail, use engine braking....as heavily and aggressively as possible. That's your life saver right there. It's very easy to use engine braking and drop speeds to a pedestrian 20 - 30 kph in little time. At that point, start using the handbrake. Don't yank it up in one strong pull, unless you are at really slow speeds; rather use it gradually. Once you are slow enough, switch the engine off (with the car still in gear) to stop. Remember : Switch the engine off only at crawling speeds as your power steering will also loose assistance.

Easier said than done, but if you have no choice other than crashing, choose what to crash into. E.g. between the back of another car & a biker, it's the car always. Shankar's suggestion of brushing against a wall / footpath to slow down is splendid!
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Old 21st March 2011, 15:17   #32
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Default Re: What to do in case of Brake Fail !!

IMHO, one should keep their calm and think logically. A damaged car is much better than a damaged limb or two.

Anyways I would like to share an incidence that happened with me. i had recently brought the w126 500 SEL and was doing some decent speeds on the highway. All of a sudden to my surprise a mahindra logan in front of me brakes hard and although i was at quite some distance i decided to brake slowly and swerve.

But to my horrer the pedal completely sank in, with no bite. I had my heart in my throat and i just glanced in the rear view mirror ,slowly pulled out the very weak hand brake lever and turned off the ignition switch as my car is an automatic and stopped the car to the road side all at he same time. Although i escaped well from the situation, i took the car on the side and checked for the culprit. the brake fluid container had developed a leak and there was almost no oil.

the first thing i did was rectify the problem after reaching my destination safely . It was really a bad experience. A combination of a v8 engine with no brakes and automatic transmission with a very weak hand brake can shatter your confidence and your ego.

After this i have made it a point that i wont drive a car until its mechanically perfect. The car now runs perfectly.

P.S the logan in front braked hard because a girl was learning to drive the car on the middle of the highway. I still blame the guy for teaching her to drive on a highway.

Last edited by konjaril : 21st March 2011 at 15:21.
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Old 23rd March 2011, 22:22   #33
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Default Re: What to do in case of Brake Fail !!

Never Mix Dot-3 and Dot-4 Brake fluid. Did you mix brake fluid? I know this is debatable, since many people claim to have mixed and used both fluids together. Tried this on my friend's Astra and his master cylinder failed.

Fluid reservoirs tend to crack when they get old. Some clumsy mechanic might have cracked it attempting to open the cap. This happened to my lancer once.

Was the brake warning / handbrake on light on before this happened?
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Old 23rd March 2011, 23:13   #34
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Default Re: What to do in case of Brake Fail !!

I was watching a program on Discovery channel a couple of days ago. I think it was 'Worst case scenario' and they covered this topic.

The advice was, in case of an open road, First Zig Zag the car and try to go on to the shoulder (gravel/sand). This creates more friction between the tyres and surface, helping you to slow down. DO NOT TURN OFF THE ENGINE. Shift to a lower gear, keeping in mind you dont stall the engine. TURN ON your head lights and hazard lights. Pump your brakes. Pull on the handbrake very slowly to avoid skidding. All this while try to zig zag the car (using gravel, shoulder etc). Look for shrubbery (avoid large trees) and drive your car sideways into it. This will help you to stop safely with minimal damage to you and car.

In case you are in traffic and realize you lost braking and your speed is below 40 mph (60kph?) Roll down your windows and shout out loudly that brakes have failed. Try pulling to the side of the road use the kerb (follow all the steps listed above as much as possible). Look for a parked Large vehicle (Truck/bus) and try to guide your car to scrape its side (wheel if possible). Or look for a crash barrier/ mesh fencing/ corrugated metal fencing and drive into it, pulling on the handbrake at the same time. The mesh fencing will absorb the impact and will slow you down very quickly.

At above 40 mph, try to slow down using your gears as much as possible before doing what has been written above.
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Old 23rd March 2011, 23:40   #35
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Default Re: What to do in case of Brake Fail !!

Zig Zag + Handbrake does not sound right to me.
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Old 23rd March 2011, 23:49   #36
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Default Re: What to do in case of Brake Fail !!

Quote:
Originally Posted by toiingg View Post
Zig Zag + Handbrake does not sound right to me.
They mentioned that it has to be done slowly, as in applied in stages. That way you dont skid but have enough friction to slow down to a safe speed where you can pull it completely. Also avoids brake fade.
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Old 24th March 2011, 00:21   #37
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Default Re: What to do in case of Brake Fail !!

Quote:
Originally Posted by anupmathur View Post
NukeBlitz, this is completely incorrect! Switching off the engine will most certainly not cause the front wheels (or rear wheels in rear wheel drive cars) to lock!
Switching off the engine is not advisable for different reasons, like loss of power assist to the steering and servo-assisted brakes.
I have noticed that Shifting into a lower gear at a higher speed does lock the drive wheels. There is considerable damage to the vehicle so avoid doing that unnecessarily.
btw someone here wrote to try out the brake while on a flyover. Please do not do it needlessly as it creates unneeded chaos as everyone brakes hard and tries to swerve out of the way.

If you are not sure about your brakes then do not drive the car.

The 800 guy whose brakes were not working for few seconds please get the brakes checked for air.
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Old 24th March 2011, 01:08   #38
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Default Re: What to do in case of Brake Fail !!

If speeds are around 60 kph or so and there is a little area to play with, a handbrake turn can also be tried. I know many things go against it. Traffic, space and the like. But maybe a possibility if real estate is there.
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Old 24th March 2011, 01:48   #39
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Default Re: What to do in case of Brake Fail !!

OT: Very very vital thread indeed. I'd urge the moderators to compile all such life threatening or near life threatening what-if driving situtions into one and make it mandatory for at least every new member to read.

Most of the points already stated are useful & effective. However, their effectiveness & deployment depend primarily on:
  1. Situation
  2. Road condition
  3. Speed
  • First & foremost one needs to know the vehicle being driven. e.g., manual vs automatic
  • Under all circumstances one needs to be calm yet alert though natural instinct is more likely to take over in desperate situations
This has been exhibited very well here:
Quote:
Originally Posted by konjaril View Post
I had my heart in my throat and i just glanced in the rear view mirror ,slowly pulled out the very weak hand brake lever and turned off the ignition switch as my car is an automatic and stopped the car to the road side all at he same time.
I'd like to augment the following point:
Quote:
Originally Posted by torquecurve View Post
The advice was, in case of an open road, First Zig Zag the car and try to go on to the shoulder (gravel/sand). This creates more friction between the tyres and surface, helping you to slow down.

In case you are in traffic and realize you lost braking and your speed is below 40 mph (60kph?) Roll down your windows and shout out loudly that brakes have failed. Try pulling to the side of the road use the kerb (follow all the steps listed above as much as possible).

At above 40 mph, try to slow down using your gears as much as possible before doing what has been written above.
Whether to manoeuvre in a zig-zag fashion or not for greater friction will depend entirely on the 3 points i have mentioned above. Obviously, Indian roads may not be as safe for such manoeuvres even if it looks reasonably empty. There could be lurking pedestrians, animals, cyclists, rickshaws etc that appear from almost nowhere. (I should know for i have undergone 3 surgeries for one similar appear-from-nowhere 'experience' on Delhi road.). However, the brighter side is one is more likely to find sand, gravel, mud, bushes etc alongside Indian roads that may offer better friction / stopping capability.

Regarding applying different techniques depending on the speed (40mph or 64 kmph) i will agree to the following comment for using the engine braking in all situations regardless of the speed, especially on slippery roads:
Quote:
Originally Posted by shankar.balan View Post
the only way to bring a car to a halt when its brakes fail is to literally ram it into the lowest available gear in the shortest time possible.
Overall, the discussion has been very well summed up crisply by GTO in the following post:
Quote:
Originally Posted by GTO View Post
The good news is, brakes rarely fail in modern cars. The bad news is, they still do (rarely)!

In the unfortunate event that your brakes fail, use engine braking....as heavily and aggressively as possible. That's your life saver right there. It's very easy to use engine braking and drop speeds to a pedestrian 20 - 30 kph in little time. At that point, start using the handbrake. Don't yank it up in one strong pull, unless you are at really slow speeds; rather use it gradually. Once you are slow enough, switch the engine off (with the car still in gear) to stop. Remember : Switch the engine off only at crawling speeds as your power steering will also loose assistance.

Easier said than done, but if you have no choice other than crashing, choose what to crash into. E.g. between the back of another car & a biker, it's the car always. Shankar's suggestion of brushing against a wall / footpath to slow down is splendid!
However, i think that one should not switch off the engine even if the car is slow enough. Should instead try to stop using the handbrakes while keeping the engine running.

Quote:
Originally Posted by Ragul View Post
For this reason, your car manual may also tell you never to switch off the engine and coast downhill.

--Ragul
I did try it once on the narrow winding downhill drive & recognised immediately the hazard posed by much stiffer steering & extremely hard brakes!

Last edited by abk : 24th March 2011 at 01:54. Reason: Typo
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Old 24th March 2011, 10:29   #40
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Default Re: What to do in case of Brake Fail !!

For AT owners will it make sense to put the stick to 1 or L when your car is at 80? Does it shift down immediately ? In case of i10, switching off the O/D switch does shift to 3rd gear and i can notice engine braking instantaneously.
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Old 24th March 2011, 13:10   #41
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Default Re: What to do in case of Brake Fail !!

^^
yes - but at the cost of transmission damage.

also, the AT car may itself choose not to lock itself into 1 or L gear, depending on the speed (to protect the transmission). so dont count your chances on it all the time.

all the more important to get the brake systems checked periodically on AT cars (that includes the handbrake system)
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Old 24th March 2011, 13:27   #42
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Default Re: What to do in case of Brake Fail !!

Quote:
Originally Posted by abk View Post
However, i think that one should not switch off the engine even if the car is slow enough. Should instead try to stop using the handbrakes while keeping the engine running.
If I may ask - Why?.

Brakes & Steering get hard?. Well, brakes are already not working, and even though the steering is hard, with all that adrenalin you WILL steer. So, isnt stopping the car ASAP the solely most important thing?.
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Old 24th March 2011, 13:46   #43
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Default Re: What to do in case of Brake Fail !!

Quote:
Originally Posted by dhanushs View Post
If I may ask - Why?.

Brakes & Steering get hard?. Well, brakes are already not working, and even though the steering is hard, with all that adrenalin you WILL steer. So, isnt stopping the car ASAP the solely most important thing?.
Please try this at slow speeds in a very controlled environment. Steering a power steering car without power steering on is not easy.

Steering older cars that had no power steering is not a good benchmark.

Also with all that adrenalin, if you end up removing the key. Things will become even more interesting. As soon as the steering locks up.
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Old 24th March 2011, 14:15   #44
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Default Re: What to do in case of Brake Fail !!

Never switch off the engine unless the vehicle, (as suggested by GTO) is about to reach 'dead halt status'. if the engine is switched off, it is extremely dangerous as Anup says, because the power steering goes almost dead. In a heavy car that is suicidal.

As GTO says, it is a good idea to gently pull the handbrake when the vehicle has slowed down considerably on account of engine braking initiated by downshifting.

As far as possible in these situations it is sensible to bang on the emergency flashing lights and while keeping a constant eye on the rear view mirrors, gently steer the car to the extreme left verge of the road - if necessary get onto the grass verge or mud or whatever and slowly bump, trundle and grind to a full stop. Or in the absence of a suitable verge, scrape the left side of the vehicle along the road barrier or wall or mud bank (in case it is a hill road or similar). Unfortunately, on our highways here, we dont have the concept of the "hard shoulder" for emergencies like they have abroad.
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Old 24th March 2011, 14:37   #45
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Default Re: What to do in case of Brake Fail !!

Slghtly

This thread reminds me of a person from my middle school days in the 70's. He started off with a cycle repair shop and developed to become a retailer of bicycles. Then he bought a second hand car. I forget the make but it was one of those open top cars with spokes in the wheels - "Motor Sundaram Pillai car", we used to call it. As far as I remember it never had sharp brakes and will come to a halt very slowly. But since he used it only locally and traffic being sparse, he managed to get by.

I never saw him drive it without some of the cycle shop boys on board. There used to be a level crossing in the place where the MIT bridge now stands, which will become visible as soon as one negotiated a not so gentle turn in the road. The distance to the gate from the bend was not very far, so if he braked upon seeing the closed gate, the car will still approach the gate very slowly.

Then he will coolly call out "Pasangala" (boys) in Tamil, and immediately a couple of them will jump out and physically hold on to pull the car to a stop before the gate! There will always be two bricks on board the car, and a third boy will run ahead and place one under each front wheel to "speed up" the process!

That was quite some technique and we children always enjoyed the tamasha!
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