I'm not a fan of ABS either. I've driven my wife's '97 GMC 2500, extended
cab, 5th-wheel hitch (not a duelie) mega truck daily 30 miles to work and
back for the past 4 years and I love it---EXCEPT for the darn ABS brakes.
Every time I'm stopping on sand or gravel or even simple bumpy surfaces
where the wheel will lift off the pavement for a split second (not panic
stops, just plain-old, every day brake use) the ABS kicks in and I find
myself traveling 10, 20 or even 30 feet farther than I intended. These
same intersections/road sections are fine in my Ford Contour that doesn't
have ABS. This can be very dangerous when you're driving in dry conditions
and haven't factored in this unexpected distance into the equation. From
what I can tell, ABS hasn't shortened my braking at all--totally the
opposite--but worse, I don't feel I've gained any additional steering
control or other advantage in return. What are we getting for this
expensive option, other than unpredictability?
Unsatisfied with the unfulfilled promise of ABS.
Alex Avery
At 09:30 AM 6/7/01 -0400, Chris Saulnier wrote:
>I'm not a big ABS fan either, I can see where a full modern ABS system would
>be a great driving aid, but the training of how to use it is so lacking...
>Personally I prefer to control brake lock with my foot, and not give it to
>electrons. Heheheh, can you imagine a Lucas ABS system? I'd never drive
>that puppy!!!
>
>Anyhow, here is what the State of Maine discovered after ABS systems started
>to be prevalent. The number of single vehicle "off the highway and into the
>trees" accidents started to rise dramatically. When they looked at the
>numbers, the majority of vehicles involved in these type of accidents were
>ABS equipped. Further study showed that most of the accidents involved
>evasive action, ie: coming up on an animal in the road at night. After some
>vehicle testing, it was found that nailing the brakes and swerving (to avoid
>an object in the road) at the same time caused the ABS systems to fully
>release the brakes. Apparently the physics of potential lock-up and slip
>angles caused the system to not apply the brakes at all during the swerve
>action. When the system recovered, the vehicle was headed off the pavement
>and into low traction surfaces (grass or loose dirt). Here, the system
>would modulated correctly, but due to the lowered surface friction the car
>would usually hit something before it stopped on the brakes. In this
>specific case, I would certainly prefer the non ABS system, to allow burning
>off speed on a high traction surface.
>
>Chris of Maine "one last post..."
>
>'71 wagon "junkbox" driver DR#5 (LZ22 :>)
>'72 4dr - project DR#6 (V8)
>'69 1600 Bluebird SSS 4dr 1/24 scale
>'70 Bluebird Coupe 30th Anniversary Edition 1/60 scale (thanks Lou!)
>
>> -----Original Message-----
>> From: Brian Hollands [mailto:bholland@hayes.ds.adp.com]
>> Sent: Wednesday, June 06, 2001 6:51 PM
>> To: Patrick P. Castronovo
>> Cc: Datsun Roadster Mailing list
>> Subject: RE: ABS
>>
>>
>> Some of the early ABS systems are easily fooled but newer
>> systems are more
>> sophisticated. The good ones will sense the speed at each
>> wheel and will
>> relieve pressure on that brake until the wheel begins to spin
>> again then add
>> pressure until it starts to lock and again release. They do this from
>> several to many times each second. So they keep the wheel
>> near its point of
>> lock up regardless of pedal pressure so that the stopping
>> distance will be
>> as short as the available traction will allow. One of the
>> problems that has
>> also occurred is related to driver training with the system. A police
>> officer was killed (If I remember correctly in a Caprice) due
>> to improper
>> training on ABS system use. The pedal will sort of vibrate as the ABS
>> system cycles between adding and relieving pressure from each
>> brake. This
>> PD had trained it's drivers with the old "pump the brakes" bit which,
>> especially with an ABS system only increases the stopping
>> distances. When
>> the driver felt the pedal vibrating under his foot he interpreted the
>> problem as wheel lock and released (began to pump) the pedal
>> ultimately
>> causing him to enter a corner too fast and lose control.
>> The pedal does feel weird when the ABS engages and that can be
>> disconcerting.
>> Brian
>>
>>
>> -----Original Message-----
>>
>>
>> I have heard some horror stories about the ABS Brakes. They
>> do not stop a
>> car on ice or sand or Gravel. Any loose soil that allows it
>> to slip and the
>> brakes release. Pat
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