ABS disconnect for snow stopping?

[strange179]

This story actually has a point.
My SVX has an ABS problem. There is a relay that will sometimes stick in the "ON" position in the ABS control box under the hood. If it sticks on the only way to shut it off is to give it a quick rap. I should fix it but I haven't yet. When it sticks on, the ABS dash light comes on, the ABS motor keeps running, and the ABS function is disabled. At that point it is as if I don't have any ABS at all. The reason that this is all relevant is that it has given me plenty of opportunities to compare ABS to non-ABS in various conditions.
I have found that ABS is generally a good thing and it has saved my butt in a couple of odd situations. I have also found that in really slippery stuff like greasy slush, packed snow, or ice the ABS really lengthens the stopping distance. I'm usually very glad to see that orange glow from the ABS light in these situations. Maybe on corners it might be good, but stopping in a straight line in slickery conditions it has caused me to "run" several stop signs with my foot very firmly planted on the brakes. I know from experience that I could've stopped if it weren't for the ABS.
Just a couple of my pennies,
Jay

[Mr. Pockets]

I disagree with you ABS naysayers. I love my SVX dearly, but let's face it - she's heavy.

I have had the SVX stored all winter, so I have been without the luxury of ABS. This week I had a problem with the Justy. I had to take the SVX for one day. Of course, it snowed that afternoon. I live on a gravel road that never sees a plow, so when I got there it was a sheet of hardpack from other people returning home. I decided I would 'make sure' that my ABS still worked after the car's three-month slumber. I was on a downhill slant, so the distance was exaggerated. But I can still say, with some confidence, that the car was able to stop itself faster and straighter than if I tried to do it myself. The car stayed arrow-straight.

Last night I drove my wife home in her Legacy. It does not have ABS. The roads were probably the slickest I've ever seen. Not snow-covered, just sheets of ice. The tires locked up WELL before I would have expected them to. Not only that, but when they did, the car did not remain that straight because they do not necessarily all lock up.

My suggestion is to let the ABS computer do what it was designed to do - stop the car ASAP and keep the car as straight as possible.

As for using the e-brake to stop, this is an extraordinarily bad idea. With the e-brake, you don't have the sensitivity that you do through your foot, through which you usually brake. This means that you will most likely cause the rear wheels only to lock up. Without a doubt, this will make you lose control. How easily you regain control (and whether or not you release the e-brake in an up or down position in your first-time e-braking panic) is up to your car control, your composure, the conditions and luck.

I speak from experience. Just for fun, I do e-brake turns in the Justy on our gravel roads - especially when it snows. It is a really horrible way to slow down - really the only reason I do it is to make the back end slide. This is not something you want to do when you're trying really hard to remain in control. The ONLY car I'll do it in is my Justy because, well, it's a freakin' Justy. If I slide it into the ditch or a tree, I'm not going to cry too hard about it.

[Mr. Pockets]

Originally posted by svx_commuter


Have you done this? I think it would really confuse the AWD system. The car would think the front wheels are spinning and the back wheels are planted....... Putting full 50% power to the rear wheels and maybe burning up the rear clutches.

I see your point that the hand brake could be used lightly to stop the car in snow.

The e-brake is entirely separate from the hydraulic, ABS-supervised, system. The e-brake doesn't even use the calipers - it is connected by cable to drum brakes on the rear wheels.

Besides that, you seems to be operating on the assumption that the AWD system detects wheelspin through the ABS sensors, and it does not. It detects this through sensors inside the transmission.

I suppose you could do some damage by applying the e-brake and throttle at the same time. Whether your transmission or the e-brake shoes would fail first, I don't know. Bottom line, I wouldn't do it.

Agian, I say that using the e-brake, especially in snow is a really really really bad idea.

Go ahead and try it if you want. But do it somewhere open like a parking lot. For crying out loud, don't you dare try it for the first time in traffic or any other potentially dangerous situation.

[Beav]

If you want to shorten your stopping distance in a car with an automatic, try placing it in neutral as you come to a stop. You won't be fighting the engine as it tries to turn the wheels. Yes, I realize the SVX shifts to accomodate that but in my experience it still helps to go to neutral below ten or so mph.

Beav

[kuoh]

Honestly, that just makes me think you overdrove the car for the road conditions. You should have plenty of warning to stop for a stop sign. It's not like they suddenly flash STOP just as you approach them. I have never ran stop signs or red lights due to the road conditions or the ABS, even on ice. And if you do rear end someone while driving on snow, well don't blame the ABS if you weren't aware of the car's normal braking capabilities. The extra few feet you "might" gain does not make up for inattention or the risk of losing control.

KuoH

Originally posted by strange179
I'm usually very glad to see that orange glow from the ABS light in these situations. Maybe on corners it might be good, but stopping in a straight line in slickery conditions it has caused me to "run" several stop signs with my foot very firmly planted on the brakes. I know from experience that I could've stopped if it weren't for the ABS.
Just a couple of my pennies,
Jay