How Get Shortest Braking Distance on Ice With ABS?

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If you have a car equipped with winter tires and ABS, which braking technique will give you the shortest braking distance on ice:

1. Stomp on the pedal, and let ABS do all the work?
2. Push lightly on the brake pedal until ABS comes on, then back off slightly until ABS disengages?
3. Push lightly on the brake pedal, but do not allow ABS to activate?
 
Braking without antilock brakes

If you don't have antilock brakes, the best way to stop is threshold braking. Keep the heel of your foot on the floor and use the ball of your foot to apply firm, steady pressure on the brake pedal to the “threshold” of locking your brakes. Remember, you must keep your heel on the floor. If your heel leaves the floor, the wheels could lock because you’re controlling the brake pedal with your thigh muscles instead of your ankle, which are incapable of finer control.

Braking with antilock brakes

If you have an antilock braking system (ABS), do not remove your foot from the brake. When you put on the brakes hard enough to make the wheels lock momentarily, you will typically feel the brake pedal vibrate and pulse back against your foot. This is normal. Do not pump
the pedal or remove your foot from the brake. The system is working as it was designed to work.

http://autoclubsouth.aaa.com/Assets/PDFs/HowtogoIceandSnow.pdf
 
How about...?

4. Don't drive on ice.


May have no choice at some point, but around here the biggest hazard of driving on ice is the other drivers.
 
I found this advice at edmunds.com:

"………………...I've battled snow- and ice-covered highways in two-dozen states behind the wheel of both passenger vehicles and 18-wheelers. I've performed hundreds of tire tests on snow-covered roads, attended snow-driving schools and done precision (translation: "barely in control") driving in the snow for videos and still photos. From this experience, here are some snow driving tips the average driver can follow to reduce the chances of a crash…………………………….

…………………... If you drive on icy roads or roads that are covered with snow, modify your ABS technique: After you "Stomp" and the ABS begins cycling — you will feel pulses in the pedal or hear the system working — ease up slightly on the pedal until the pulsing happens only once a second……………………..

http://www.edmunds.com/car-safety/driving-on-snow-and-ice-10-safety-tips.html
 
The ABS will do a pretty good job on a really slick surface, but an experienced driver can do better.
Light and gradual pedal application with a skiiled driver is probably better, but I've often had to pump the pedal hard w/o ABS to allow steering under braking on really slick surfaces.
Those who grew up in the north understand this.
Those who didn't can learn.
The main benefit of ABS is that it allows steering control.
It doesn't produce shorter stops.
 
From a Nov 2011 article, written by Ian Law at Car Control School in Canada:

"………….Here is a fact that catches a lot of motorists by surprise: if the vehicle we are driving is equipped with ABS brakes, our stopping distances on ice and snow will be longer than if our vehicle did not have ABS brakes. In older vehicles and less expensive vehicles, ABS can lengthen our stopping distances by up to 50 per cent compared to non-ABS. In more modern vehicles and, in particular, ones with very sophisticated ABS braking systems, the difference is not so pronounced…………………"

"……...We all have to give our braking the respect it deserves. In winter conditions, slow down and leave more space for the vehicle in front…………"

http://www.wheels.ca/news/abs-brakes-can-add-to-stopping-distances/

http://www.carcontrolschool.com/winter-driving-school/
 
All the more reason, especially around here, to avoid driving on ice at all costs. I don't have enough routine experience to do it well and most drivers around here can't even do well on dry roads.
 
Originally Posted By: bourne
3 if your good at braking, 1 if youre not


I also agree with this but would like to remind you to take advantage of surface irregularities and if you really need it, safely bouncing off of things also can help.
 
Originally Posted By: SubLGT
From a Nov 2011 article, written by Ian Law at Car Control School in Canada:

"………….Here is a fact that catches a lot of motorists by surprise: if the vehicle we are driving is equipped with ABS brakes, our stopping distances on ice and snow will be longer than if our vehicle did not have ABS brakes. In older vehicles and less expensive vehicles, ABS can lengthen our stopping distances by up to 50 per cent compared to non-ABS. In more modern vehicles and, in particular, ones with very sophisticated ABS braking systems, the difference is not so pronounced…………………"

"……...We all have to give our braking the respect it deserves. In winter conditions, slow down and leave more space for the vehicle in front…………"

http://www.wheels.ca/news/abs-brakes-can-add-to-stopping-distances/

http://www.carcontrolschool.com/winter-driving-school/




Not always. There is the logic that not having ABS allows snow to bunch up in front of the wheels, slowing it down faster. The guys at Tire Rack have told me off-the-record that this isn't necessarily optimal with newer tread designs and compounds.

I will say this: having tires that are rated for traction on ice will go a LONG way. All-seasons generally are not rated for that.
 
There are some significant brake bias differences in some modern ABS equipped vehicles. Front and rear brakes may have more similar initial torque. Due to these differences, the rear brakes have more initial stopping power than conventional older vehicles. These cars and trucks will sometimes rely on the ABS to prevent rear wheel lockup before the fronts even think about losing traction.

This gives a nicer braking feel to many cars.

Experienced drivers will notice that only modest ABS engagement is in play, and the fronts are not yet at the threshold limit. Much of this depends on tire compound, road conditions, vehicle loading and weight transfer.

This means that under some circumstances, threshold braking may not be the fastest deceleration rate.


Not sure how this translates to stopping on glare ice. And, better vehicles are tuned to reduce ABS authority at very low speeds. Allowing modest wheel lockup for snowy conditions.
 
Originally Posted By: SubLGT
If you have a car equipped with winter tires and ABS, which braking technique will give you the shortest braking distance on ice:

1. Stomp on the pedal, and let ABS do all the work?
2. Push lightly on the brake pedal until ABS comes on, then back off slightly until ABS disengages?
3. Push lightly on the brake pedal, but do not allow ABS to activate?


4. Plow into snowbank-tree-whatever is available.
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I have about a month on my General Arctic Altimaxs on my Sable. When we had an icing event around here, I was able to get around OK, and the ABS didn't kick in, due to having actual traction.
 
Originally Posted By: Wagonmaster261
I have about a month on my General Arctic Altimaxs on my Sable. When we had an icing event around here, I was able to get around OK, and the ABS didn't kick in, due to having actual traction.


Can you elaborate on "able to get around OK"?
 
Originally Posted By: Cristobal
For the shortest braking distance, drive as slowly as possible.
A little basic, but yah. only different. In slippery weather, it really pays to extend your safe following distance so you dont need to mess with braking, period. In younger days, I drove cars with faulty brakes.Trucks, overloaded to the point of making the brakes useless. Same strategy applies in both situations. You just make darn sure to not put yourself into a situation where brakes will be required. If you are worried about stopping distances on ice, you are overdriving the conditions.
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Originally Posted By: Wagonmaster261
………….I have about a month on my General Arctic Altimaxs on my Sable. When we had an icing event around here, I was able to get around OK, and the ABS didn't kick in, due to having actual traction.


Studded?
 
My personal experience is applying brakes hard enough so they engage ABS and then easing off so it works intermittently.

ABS is not created equal. Our Subaru(no stability) has a very primitive system compared to my 07 MDX. On the Subaru if two wheels lock on one side of the car due to ice and pavement the other they all go into ABS and overextends stopping distance. The reality is the stopping distance would not be that much worst with two wheels on pavement. Its annoying.

My Acura MDX simply applies them at proper wheel.

That being said it is ABS system dependent.
 
On modern cars with all the computer and traction aids you don't need to help them, the computers can and do, do a better job than a human can. Stomp the pedal and let the aids figure it out.

Oh and tire chains or studs, those will help more than anything.

I was driving a big new Lexus LX in some slippery icy snow and I couldn't beleive how good it was. Compared to my truck with just ABS modern vehicles are soooo much better. I can drive in the snow just fine without all the aids and I have, mostly with RWD cars. But its nice having the technology because it does work and it does stuff that a driver just can't. Like brake individual wheels at different rates etc.
 
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Originally Posted By: rjundi
………...On the Subaru if two wheels lock on one side of the car due to ice and pavement the other they all go into ABS and overextends stopping distance. The reality is the stopping distance would not be that much worst with two wheels on pavement. Its annoying…………………..


IIRC you have a 2005 Legacy? It has a 4 sensor, 4 channel ABS system that operates each brake independently. The 2 tires on the dry pavement should not be going into ABS mode.
 
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