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Pumping ABS brakes

I just completed my driver training. They mention some where in there, that you should never pump ABS brakes. They say that you should firmly press on the brake pedal and not pump them, as, that could cause them to fail. My dad on the other hand, says that that is not true, and you should always pump your brakes, especially when stopping suddenly. Any thoughts?

Both are wrong to some degree, but your dad is more wrong, technically. In theory, you should not pump the brakes, if you do, they will not fail, you will just override the ABS and then you have to keep pumping the brakes to keep the brakes from locking up.

However, I am not a fan of ABS. I have found that if both wheels on one axle lock up at exactly the same time, the ABS will not work any you will spin. I had this issue on my Nissan PU when it was brand new. I had to pump the brakes to keep the rears from locking up. Eventually as wear and tear caused differences in the rear brakes, this problem went away.

Pumping will not cause them to fail.
Pumping will also not help you to stop or to maintain control whil stopping.

ABS is designed to do your pumping for you. Press and hold the pedal and the ABS system will do your pumping for you. You should not pump the pedal.

HOWEVER; when you’re in your dad’s car and he’s with you, you should always pump your brakes. His car, his rules. It’s harmless, So follow his wishes.

If you have to stop suddenly, your mind isn’t likely thinking about pumping the brakes to begin with.

Found out my 99 Nissan PU,would stop better in the snow,if I fanned the brakes a bit.This vehicle had 4 wheel ABS and it really didnt want to stop when it was slick(ABS is more about directional control anyway,it was originally developed to keep aircraft on the runway)-Kevin

You will normally stop faster just holding the brakes down on ABS, but the world is full of things we do not expect. Your seat of the pants will tell you more what to do when you need to stop than any engineer.

Just push and hold the pedal and let the ABS system work. By the way, the main function of the ABS system is not necessarily to stop you faster. It’s to keep the wheels from skidding so you can still steer your car and thereby hopefully avoid collision.

You should not pump ABS brakes, with the exception of trying to stop on ice. On sheer ice, you probably won’t stop anyway, but this surface seems to confuse some ABS systems, especially older ones and the “2-channel” ones on some pickups. On this surface, pumping the brakes may help you stop sooner. IMHO, the best thing you can do is to find a nice slippery parking lot after a snow, with plenty of space so you can’t hit anything, and do a few hard practice stops with your ABS. This will familiarize you with the sensation of it kicking in and working, and you can try pumping the brakes to see what that adds to the equation too.

Pumping abs brakes is the act of a control freak. People who advocate this dangerous practice which increases stopping distance over abs equipped cars, just never had enough experience with them. The need to go to an icy parking lot with cones and have at it.

Abs pumps the brakes for you at a rate even a race car driver couldn’t replicate. Why do the vast majority of the most talented drivers in the world recomend them on their own family cars, while, the ones most in need, we olderfarders campaign against their proper use ? Ignorance !

Oblivion…I disagree. Sheer ice is when you most need it. Locking your brakes on ice creates a water film the same way ice skates do making it harder to stop. All ice is not the same. The colder it is, the more friction you can create by using abs. It’s wet ice that is the most slippery and even then, a rotating but slowing tire has more friction then one that is locked.

"euryale1
Your seat of the pants will tell you more what to do when you need to stop than any engineer. "

This is a dangerous assumption. The seat of your pants will also tell you that the airplane you’re piloting is climbing, when in fact you’re in a dive. In that case the seat of your pants will get you killed, but following the cold, hard data presented by your instruments (or letting the autopilot do its job) will keep you out of trouble.

ABS is designed to do the pumping for you…but at a greatly increased rate.

And the few times in the past 10 years I still find myself pumping my brakes in a panic situation (like when the girl next to me is texting and then realizes her exit is 100’ away and crosses 3 lanes of traffic).

It won’t do any harm…but it also won’t work as well as just leaving your foot planted on the brake.

Here’s a good article comparing summer, ‘all season’, and winter tires on snow. Note the comment on how the ABS couldn’t help the summer tires on snow:

Your dad’s theory is out-of-date. ABS will pump the brakes for you.

I’m going to let it go boys.when it gets icy the best thing to do is stay home or drive very cautiously.I do know the early Gov’t mandated ones on trucks werent worth a hoot,most everybody had to disconnect them before they run over someone.I think and hope the new systems work better-Kevin

We travel a snow over ice covered mountain dirt road due to the frost which starts in December and continues through February. We travel over this road daily with studded snow tires and awd and 4 wd cars and trucks. There are times during ice storms when the only thing that moves are peolple wearing ice grippers and awd cars with studs. You can go on glare ice if you drive slowly and come prepared.
I mount 80 of these things instead of chains each winter on each tire of my tractor to remove snow…they work.
http://images.search.yahoo.com/search/images?_adv_prop=image&fr=ipad&va=ice+studs+for+tractors

I’ve had situations in my Odyssey when the ABS would not bring me to a complete stop going down hill in snow. I had to modulate the brakes so the ABS didn’t kick in to stop. When someone’s back bumper is coming at you , this can be scary!

a care with abs brakes just put steady pressure on the pedal and let the abs systemn do its job. by pumping the pedel yourshelf that will reduce your stopping distance so keep pressuree on the pedel.