Order Jeep -> Lose Rebate??

On 09 Dec 2003 03:00 PM, Paul Brogren posted the following:

If you don't know how to operate an ABS equipped vehicle, then yeah, the stopping distance will be longer. It is difficult for somebody used to driving non ABS rigs to just mash the pedal down and hold it while the system does its work. The natural reaction is to let up, since that is what you do with conventional brakes, but it is exactly the wrong thing to do, and WILL lead to longer stopping distances.

---------------------------------------------------- Del Rawlins- del@_kills_spammers_rawlinsbrothers.org Remove _kills_spammers_ to reply via email. Unofficial Bearhawk FAQ website:

On 09 Dec 2003 10:31 AM, Mike Romain posted the following:

The increased stopping distances are a reflection of a lack of driver training with the new equipment, not of any problem with the ABS systems. You and I are not physically capable of outbraking a properly set up computer.

---------------------------------------------------- Del Rawlins- del@_kills_spammers_rawlinsbrothers.org Remove _kills_spammers_ to reply via email. Unofficial Bearhawk FAQ website:

On 09 Dec 2003 02:21 PM, CRWLR posted the following:

That is easy enough for somebody living in southern california, who will never have any use for ABS to say. In snow and ice, ABS can be a real asset and after having it on my last 2 rigs, I wouldn't buy a new vehicle that didn't come with it. When was the last time you drove to work on icy, snow covered roads? I've been doing it every morning for the last month and a half and I like having ABS on my Jeep. Sure, a good driver can and will get by just fine without it, but it can be a valuable thing to have on occasion when the guy ahead of you does something dumb. Then there was the day that I tried to make that right hand turn too fast in my S-10 on the ice a few years ago. The ABS took me right around that corner and even kept me in my own lane; with standard brakes I most likely would have slid across the intersection and into the ditch, a victim of my own stupidity.

As for the D-44 with ABS, you just can't get it that way from the factory. The aftermarket can provide you with an ABS equipped D-44, but you can expect to pay for the privelege of having your cake and eating it too.

---------------------------------------------------- Del Rawlins- del@_kills_spammers_rawlinsbrothers.org Remove _kills_spammers_ to reply via email. Unofficial Bearhawk FAQ website:

Or even most of the ones out there. With the disclaimer that there are some surfaces where ABS will slow down a stop...none of which are encountered on public roads. Two things cause the increased stupidity count with ABS.

1. In most of the accidents with ABS equipped cars, the driver never hits the brake pedal hard enough to engage the ABS.
2. Drivers simply overdrive conditions if they know the vehicle is ABS equipped.

LOL!

Sure..... and Microsoft has the market cornered....

A total lock of the wheels is the fastest stop, period.

Threshold braking allows some control if needed. People aren't taught this.

ABS refuses to lock the wheels period. If you are on a real steep dirt or snow down hill, you will not be able to stop period.

The tree or car at the bottom 'will' stop you fast though. Been there, watched that, then watched the second and third try with the ABS fuse pulled. He could then miss the tree.

Just go read the real stats on ABS from the national transportation safety council that Bill posted.

The insurance companies also have similar studies and stats out.

ABS is crap in emergency situations where you need a fast stop. It works well if you have the room or time to react. It is plain dangerous off road.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's

Del, the makers even state ABS has a longer braking distance.

There isn't any debate on that issue, do a google search.

It is not operator error, it is a defective attempt to compensate for drivers that were never trained how to drive.

Same for air bags. Ever wonder why they are designed to stop an adult with no seat belt on? To compensate for fools on the roads.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's

Del Rawl>

On 09 Dec 2003 05:19 PM, L.W.(?ill) Hughes III posted the following:

If road conditions are such that you can melt rubber, then you are right, there isn't much point to ABS. It is when the roads are nasty, icy, sloppy, and wet that ABS comes into play. I'm sure you see those conditions frequently down there in California. What ABS can do, that no human being is capable of, is simultaneously keeping all 4 wheels at the point of maximum braking. The best you and I can manage, is to keep the wheel with the least grip from locking up, which means that the other 3 are not braking to their greatest potential.

I'm not really sure what it is you are trying to say here. It sounds as if you have found a statistic and are then making up your own assumptions about the cause. Even accepting at face value that ABS equipped rigs are involved in 30% more fatal crashes, it could easily be explained by the inability of the driver to corrrectly operate ABS equipped brakes. It could also mean that the drivers felt that they could drive too fast for conditions because they had ABS. I personally believe that these two explanations are far more plausible than what you are describing, based on my experience with ABS.

---------------------------------------------------- Del Rawlins- del@_kills_spammers_rawlinsbrothers.org Remove _kills_spammers_ to reply via email. Unofficial Bearhawk FAQ website:

No, I have a Mazda MPV. I ate lunch waiting for it to stop.

Don't be so optimistic. Microsoft Windows Automotive 4.2 operating system is yet another onslaught now that Windows CE Automotive has managed a few applications.

And if you love the direction DC is taking Jeep,

For pretty much all drivers, probably as true as it gets. For folks and vehicles with decent feedback, not that true, as next sentence implies.

People *are* taught this. However the only place I've ever been taught this was in racing schools. And even some race drivers will admit that on public roads, they themselves may just lock em up in high puckerfactor situations...as long as the vehicle keeps in a straight line. Which most vehicles will do when all 4 tires are sliding free due to lockage *if* it was started at a high enough speed and brought on quickly enough so none of the wheels grab. And then let go as speed drops to where differences in tires or road surface begin to move the vehicle off a straight line path. ABS can help with this phase as it can detect a skidding wheel long before a human can and can release that wheel far faster than any human can, and then reapply max braking long before any human can. *IF* the human knows how to use ABS systems, which most don't.

Only if you manage to keep the vehicle above the threshhold speed at which the ABS automatically disengages.

May be worth while reading some of the backing data as to why ABS is useless on most vehicles... the driver never engages it or is overly optimistic in what it can and can't do.

And backing data as to the causes, which have more to do with poor driver training than ABS itself.

False. If the driver isn't a doofus, it will stop faster than anything but a very very skilled race driver....except where wedging of the surface material is available.

False and falser. If you have limited time to react, simply stomping on the brakes hard enough to engage the ABS and keeping your foot there will stop any vehicle faster than a skidding tire will... on most surfaces. Unfortunately few people ever engage it, and most of the ones that do tend to panic and take their foot off at the worst time.

A bit strongly worded, but close enough to true.

Oh pavement, stopping distance is decreased when the tire is at maximum friction. A tire reaches maximum friction just as it is about to start sliding. ABS tries to keep keep the tire at its maximum friction level, therefore stopping the vehicle faster on pavement. Its simple (or maybe not) physics. When you hear a tire squealing, its because it has started moving with respect to the road which means that its taking longer to stop had it came to the point just before squealing.

Note that all this does not apply to situations in which a locked tire can dig into the ground when ABS is bad because it keeps your tire from digging in.

I'll stop getting ABS on my vehicles when the lawsuits keep the manufacturers from offering it.

message

Finally!

Lots of 'if's' in there eh.

I raced when I was young so likely have an advantage over most drivers when it comes to braking. 4 wheel drifts around corners was one of my specialties....

Mike

L>

Geese guys, all the studies and the makers of the damn things say they take longer to stop than manual brakes in a straight line stop like one sees in traffic. Period!

They sacrifice some stopping distance for extra control.

Simple concept. Makes total sense to me.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's

Valued User wrote:

If the computer is purely ABS, that may be true for you, but it has been proven to be not true for everybody. Particularly in off-road situations where even a lockwheel stop is faster than an ABS one--with today's control systems for ABS. And on some slippery surfaces, racing drivers can beat ABS sometimes.

As for training, lecture style training even with visual aids and movies has demonstrated no improvement in driver use of ABS. They still do it wrong. Which may be why it is impossible to get a racing license without instructor observed track time where you bend the shiny parts until you figure out how not to.

Seems the biggest contribution to ABS accidents is that the ABS allows the driver's insanely suicidal steering inputs to actually have effect, whereas the same driver without ABS will usually have the front wheels skidding enough that steering input has far lower effect. Plus the drivers refuse to trust the ABS and keep it engaged. Braking time for ABS enabled is often slightly less than for disabled.

Which is why some vehicles have added yaw and slew rate controls on top of ABS... drivers with none of the mandatory "body learning" type experience it takes to learn how to use ABS...or not use it.

Unfortunately, for the typical driver this is not the safest condition if the driver is attempting to avoid something. Sliding wheels ignore driver steering input, ABS cycling wheels allow suicidal inputs. In actual crash statistics, the driver's excessive steering is more dangerous than simply skidding more or less straight ahead.

It isn't that simple. Many tires, particularly complex tread high performance ones will play an entire symphony of tones as their slip angles increase to the point where the tire tread essentially becomes uncoupled from the road surface. Highly useful tunes if you've managed to explore your tire and vehicle limits...which can be pretty hairy in a high Cg vehicle.

Don't get me wrong, ABS is a great thing to have. But, its main function is to maintain directional stability (which you illusatrate very well), even if the expense is a possibly longer stopping time and distance. Face it, if the choice is sliding sideways down the road, or steerinig around an approaching obsticle, I'll take the steering around stuff any day, even if it adds a few feet to the stopping distance.

That's what I meant. It is not an available option from the factory.

Except that it is a misstatement of fact and a contradiction of the SAE test results except on wedgeable surfaces. And worse ignores the fact that the extra control itself contributes to the fatalities.

Other than that I guess it could make sense if you'd actually take the time to read the SAE tests where ABS does indeed stop faster most of the time and where they also figure out why the typical driver with ABS doesn't. Something ABS by itself can't cure.

On 09 Dec 2003 07:17 PM, Lon Stowell posted the following:

I will never have the ability to modulate the pressure applied to the calipers and wheel cylinders individually like the ABS system can. Also, I may do pretty good on a good day, but I may not be having a good day. The computer has the same day, every day. On my previous rig, when the ABS computer was having a bad day, it reverted to standard brakes and the warning light came on advising me of this.

One thing which I read once but haven't taken the time to confirm, is that ABS is banned in formula one racing because it allows mediocre drivers to be competitive with the better drivers.

Well, that is the problem with lecture style training. It needs to be followed by practical training. I personally have practiced on deserted roads and parking lots to get a feel for how the ABS reacts when I am not in danger of hitting something. My reaction to the ABS isn't yet as fast as my reaction to a skid (guess which I spend more time practicing, heheheh), but I don't have to think about it either, I recognize the hum and mash the pedal.

Just because the training used is not effective, doesn't invalidate the concept of getting training. Another thing which I do and recommend, is occasionally TEST the ABS to make sure it is actually still working before it is needed.

Once again, that is an issue that could be solved through effective training. Probably never will, but it is hardly the fault of the mechanical device in question.

I always say that if you can't make the leap of trusting the system, that you are better off without ABS. What I find particularly dangerous, is switching between rigs that have it and those that don't. That is one of the reasons that my one wheel drive pickup is parked until spring, in addition to the fact that it is a slug in the winter and lacks the traction to get out of its own way.

Eventually they will probably invent a vehicle which will totally take driving ability out of the equation. I'm only in favor of that if they will still let me drive my old stuff on the road.

---------------------------------------------------- Del Rawlins- del@_kills_spammers_rawlinsbrothers.org Remove _kills_spammers_ to reply via email. Unofficial Bearhawk FAQ website: