FORANA

Hey gang. How likely is it for ABS to malfunction? It might be just bad driving but here's what happened:

I was coming down the highway and some retard in front of me stopped suddenly for a pedestrian who was not even in the crosswalk. So we went from 40mph to 0 very suddenly. It was raining. I hit the brakes pretty hard and the ABS kicked it immediately. It was a grinding noise and I could feel it in the brake pedal. I felt like I didn't stop as fast as I should have even with the wet road. I came like 2 inches (literally) from hitting him.

Do you think thats just how the ABS is or is it likely that there's something wrong? Anyone else have trouble? Or maybe I am just a moron!

Thanks gang!

mastacox

Sounds like your ABS system saved you from certain doom. You would have rear ended the guy for sure without it, especially with an emergency stop in the rain!

seanz0rz

yea i had to use my abs in the rain a few weeks ago... mine made a grinding sound too, i guess its normal. this is the first time ive ever used abs, i usually allow plenty of space between me and the guy in front of me, but a BMW cut me off on an interchange road.

gapboi210

The sound is normal. That is the sound of the pump pulsing. Also ABS does NOT make you stop in shorter distances. It keeps the wheels from locking and ables you to keep steering control.

mastacox

Not true, ABS significantly decreases stopping distances, since static friction on your tires is greater than kinetic friction. ABS enables a person to stop far faster than with a non-abs vehicle.

The Saleen S7 gets killed by a Porsche 911 Turbo in a 0-100-0 because the S7 doesn't have ABS, even though it accelerates to 100 mph much faster due to the large horsepower advantage. Why? The driver of the S7 is forced to try "pumping" the brakes, but in the end ABS pulses a LOT faster.

X2and4X

ABS is just another Driving aid. As for racing, an ABS car is not always welcome. It comes down to the driver. For a novice racer, ABS can be helpful. For the experienced driver it gets in the way. A brake proportioning valve is much more helpful when you start really pushing the car to the limits of it's braking.

gapboi210

Most cars do stop shorter with ABS but that is not the purpose of it. Speaking of braking I was reading that the new Mercedes has some cool things like this:

Brake Assist (BAS) BAS senses emergency braking via the speed at which the driver presses the brake pedal and immediately applies maximum available power boost, potentially reducing the overall stopping distance by eliminating the delay caused by a common human tendency not to brake hard enough, soon enough. Letting up on the brake pedal releases Brake Assist.

TFJ-4runner

This site should help to clear some questions. http://auto.howstuffworks.com/anti-lock-brake.htm

hiloracerboy84

yeah thats your abs working for you. it may not have seemed like it slowed you down faster, but like said, it helps with keeping you under control. i know it doesnt always help though, depending on the conditions and stuff. depending on your vehicle too, your abs may be sensitive. my 97 sr5 always does that with the vibrating pedal, awkward noise thing. my moms 00 limited never has the problem though. i even tested it on a hill near my house. going down the hill braking for the stop sign and running over a manhole cover when wet, my 4rnr always has the abs kicking in, sending me past the stop sign. my moms runner on the other hand doesnt have the problem and always stops perfectly. i guess the computer on mine is a litle more sensitive. but yeah abs doesnt ALWAYS let you stop faster. i find it a p.i.t.a. a lot of times. anyway yeah. oh n btw i have pretty new revo's and my mom's has the dueler h/l's, so i dont think its the tires

gapboi210

maybe the tires too. she may have better traction. or different suspension.

rimpainter.com

It wouldn't hurt to pull your rear drums and have a look just for kicks. Chances are you might find a leaky axle seal (thus gear oil-soaked shoes) and maybe unevenly worn shoes. A simpler test is to pull your e-brake slowly with no other cars around and see how well it brings your vehicle to a stop. With fluid-soaked shoes pulling the e-brake won't do much. Ask me how I know!

HAVOC

gapboi is right, ABS allows the driver to retain steering control. The decreased stopping distance is also an added benefit.

gapboi210

grease or oil on the soes does not always mean the rear breaks wont work. in some cases it will cause the shoes to stick and lock up. brake fluid udually does this when leaking from a cylinder.

FORANA

Yeah Hiloracer, my ABS kicks in way too much. I can hit a bump while braking and it'll kick in way too prematurely. That what happened to me when I almost hit the dude, I hit a bump and ABS kick in when it was not needed, actually making my stopping distance longer.

Funny thing, I picked up an old Popular Mechanics last night. It was an article about how your bright ideas are bad ideas. The second item said tires larger than factory recommended sizes causes the ABS systems to function poorly. I guess the computer's calculation of wheel spin gets thrown off.

Next time I'm getting 265/70s.