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Toyotaman said:
By the way isn't the whole purpose of ABS to help you maintain steering control while stopping? I didn't think it was meant to stop you any faster, but to allow you to control the vehicle's path because you can't in a skid.
Right, but using threshold braking also maintains steering control, thats the key: Maximum braking power while maintaining directional control. Also, with the ABS pumping you have less steering control than if you are properly braking at the threshold.

Now, I don't want to promote everybody ditching ABS and VSC if they haven't been to trained in emergency maneuvers, if you don't know how to apply the skills I have been talking about (nothing wrong with that,the vast majority of drivers can't) , please, please buy this safety equipement. For your safety, the safety of your family, and the safety of other motorists and pedestrians.
 

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Toyotaman said:
"A TRAC" is the same mode as AWD or Full-Time 4wd...there are two many damn names for the same freakin thing. Locking any diff, center or rear, will cancel this mode. A Trac is the selection to go from 4x2 to AWD and then locking the diff will make it 4wd with NO VSC OR TRAC.
A-Trac is only the traction control system that brakes the spinning wheel to divert power to the other. It is independent of the other systems and works in 2WD, 4WD, locked or un-locked diff. Obviously, if the diff is locked, it will only have an effect on the front axles. They used the A-Trac alot when they ran the Rubicon and it worked very well and was very helpful. Switching from 4x2 to 4x4 is done manually with the transfer case lever. You cannot switch from 4x2 to full-time 4x4 as these systems are not offered on the same vehicle with the same transmission.

All information courtesy of the FJC Product Manager I spoke with at Ojai, and my experience while sitting in the vehicle.

Jason
 

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n6opv said:
A-Trac is only the traction control system that brakes the spinning wheel to divert power to the other. It is independent of the other systems and works in 2WD, 4WD, locked or un-locked diff. Obviously, if the diff is locked, it will only have an effect on the front axles. They used the A-Trac alot when they ran the Rubicon and it worked very well and was very helpful. Switching from 4x2 to 4x4 is done manually with the transfer case lever. You cannot switch from 4x2 to full-time 4x4 as these systems are not offered on the same vehicle with the same transmission.

All information courtesy of the FJC Product Manager I spoke with at Ojai, and my experience while sitting in the vehicle.

Jason
fair enough...you've seen it and touched it and smelt it...I submit. I am only going on the experience I have had with other toyota products and what the reps have told me so far. But you seem to have done better and more efficient homework...well done and thanks for the education.
 

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Interesting thread... I guess I'll throw in my 2-cents worth. I like ABS, but hate skid control systems that try to adjust your "driving". ABS has saved me twice over the years (from rear ending others). My Porsche Boxster S had some kind of skid control system that would kick in when pushing the limits on mountain roads. It had a habit of locking the outer front wheel while turning hard and it always threw the car towards that side. When your on a mountain road with a cliff on the outside of the turn and that damn system kicked in, your heart would jump right out of your chest when it pushed you towrads the CLIFF! (just for an instant) You could turn it off (and I frequently did), but it always reset when the car was turned off. It was hard to remember to turn it off when you get a spur-of-the-moment wild hair... So, my preference is ABS for sure, but a turn-off switch for other systems that are forced on you.
 

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mpd8488 said:
Right, but using threshold braking also maintains steering control, thats the key: Maximum braking power while maintaining directional control. Also, with the ABS pumping you have less steering control than if you are properly braking at the threshold.

Now, I don't want to promote everybody ditching ABS and VSC if they haven't been to trained in emergency maneuvers, if you don't know how to apply the skills I have been talking about (nothing wrong with that,the vast majority of drivers can't) , please, please buy this safety equipement. For your safety, the safety of your family, and the safety of other motorists and pedestrians.
Can someone please explain to an ignernt Texan what threshold braking is? Sorry if this has already been covered.
 

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weisguy, threshold braking is a method of braking that utilizes as much as the cars stopping power as possible. The threshold that threshold braking refers to is litterally the brink of braking force applied just before the wheels lockup. If you lock up your wheels and skid, you have zero steering control, you can't turn the car a bit especially when braking from highway speeds. It's basically braking the car with as much braking power as possible without the wheels locking up. You can feel the threshold through feedback in the steering wheel and brake pedals. Its hard to describe what it feels like, it needs to be experienced. It is not difficult to do or learn, but it should be learned with a profesional instructor on a closed course.
 

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So it's what most of us have been doing since we could reach the pedals. Didn't know there was a term for it. Thanks for brawdnin my vocabalary. :cool:
 

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weisguy said:
So it's what most of us have been doing since we could reach the pedals. Didn't know there was a term for it. Thanks for brawdnin my vocabalary. :cool:
Actually, No, sure anybody can brake hard, but I am talking about litterally pressing the brake, and holding it at the point JUST before the wheels lockup. Like I said its not difficult to learn, but it does have to be learned and experienced. Nobody can do it without actually having first learned it with a profesional driving intsrtuctor first. I don't mean you typical drivers ed/behind the wheel teacher, I learned on a race track with an accident avoidance school in police spec Chevy Caprices.
 

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mpd8488 said:
Actually, No, sure anybody can brake hard, but I am talking about litterally pressing the brake, and holding it at the point JUST before the wheels lockup. Like I said its not difficult to learn, but it does have to be learned and experienced. Nobody can do it without actually having first learned it with a profesional driving intsrtuctor first. I don't mean you typical drivers ed/behind the wheel teacher, I learned on a race track with an accident avoidance school in police spec Chevy Caprices.
I taught myself in an abandoned parking lot in a 1980 RX-7. Man could that thing drift corners! I will say, however, that had it been equipped with ABS or traction control, I'd now be dead rather than hanging out here.
 

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Jesus, I have something like 9 years post high school education and you guys have me feeling like a German taking a Spanish quiz. A) Can I take my 3 kids, 2 dogs, and 1 beautiful wife wheeling without killing them in the first 60s? Can I get a "loaded" FJC capable as a daily driver and experiencing the outdoors with a couple of poor man's river explorations and camping expeditions planned without getting an H3, LR, or LUXO LC? I'll take all the bones the industry will throw me inregards to VSC and airbags, but don't want unnecessary crap. No offense, but the salesmen will get $500 over invoice or no sale. I am willing to pay them for their effort but I have a lot more patience than they do...A
 

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MDCruiser said:
Jesus, I have something like 9 years post high school education and you guys have me feeling like a German taking a Spanish quiz. A) Can I take my 3 kids, 2 dogs, and 1 beautiful wife wheeling without killing them in the first 60s? Can I get a "loaded" FJC capable as a daily driver and experiencing the outdoors with a couple of poor man's river explorations and camping expeditions planned without getting an H3, LR, or LUXO LC? I'll take all the bones the industry will throw me inregards to VSC and airbags, but don't want unnecessary crap. No offense, but the salesmen will get $500 over invoice or no sale. I am willing to pay them for their effort but I have a lot more patience than they do...A
A) Yes, however the hot wife will be asked to stay here and keep us company while you're away. ;)

Even stock, they are supposed to be fairly well equipped. We don't really have an accurate list of available options just yet. The stock FJ took Rubicon though so if your only worried about transporting that family to an outdoor location - you should be okay.

You seem to be in the same boat with the rest of us - praying for a la carte options instead of unnecessary package offerings. It seems only time will tell.
 

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mpd8488 said:
I was able to stop a police package Chevy Caprice (one heavy ass car, mind you) from about 75 mph in about sixty-seventy feet.

Those systems were designed for all the people who don't know what to do behind the wheel if an emergency arrises. There is no emergency vehicle handling taught in the U.S. so hardly anybody knows what to do in those situations. A lot of people get lucky, but hardly any know what they are actually doing in an emergency maneuver.
Do you really think that first statement is even NEAR being true??? An F1 car can meet that 67' from 75mph but NO production car in the world can get even close, not an Enzo, not an Elise, not an Ameritech F1, none of them can get even close to 100 feet from 75mph! That is so wrong it hurts.

The second statement is just as BS loaded. Formula 1 cars (I think Kimi, Michael and Fernando are probably "slightly" better drivers than you are) use traction control and would use ABS but it is not allowed by rule (to prevent faster lap times). WRC uses traction control also.

The biggest problem with what you proclaim is the fact that ABS produces longer stopping distances than threshhold braking, this is completely false. Even in the best conditions drivers that have spent their entire lives racing at the top level of road racing can't get better ABS equipped stopping distances using all their talent.

Traction control varies much more depending on the "tuning" of the specific program, which is very different in say a Civic compered to an F430. Traction control/stability control in the F430 or a Z06 will let you hang the back end out a bit more before reeling you back in. The FJ will have a quicker acting system but outside of off roading or in the hands of a driver with the car control skills of a WRC driver traction/stability control systems are safer for less than 1 out of 10,000 drivers. Even though I have been tracking cars for over 20 years I NEVER drive on the street with traction/stability control defeated on any of my cars, if you feel the effects of traction control on the street you need to adjust your speed/steering inputs for the conditions. These systems are there to help safeguard you in unanticipated conditions and unless the driver is the one driver in the world that has exemplary skill AND has 100% concentration on driving all the time they are effective safety tools, to suggest otherwise is folly.

Rant over.
 

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You are absolutly right about the braking distance I said, I actually pulled that number from a different activity we did during the course, oops. The braking distance was much, much, longer than what I said before, but it was still better than with the ABS on, and much, much better than having the wheels lock up.

ABS is not designed to shorten stopping distances, though it does shorten distances compared to wheel lockup, it is designed to maintain steering control. ABS in a standard passenger vehicle only uses about 75% of the vehicles braking ability, while threshold braking can allow you to utilize over 90% of the cars abilities. It is better to be able to steer around an object in an emergency, even if it means compromises the braking distance just a bit.

The traction control systems in high end performance vehicles and racecars are going to be completely different than you standard sedan or SUV. The sytems in a corvette or a porsche, for example, might only engage when the computers sense that you are just about to cross the limits of your traction, while a system in a car won't let you get anywhere near the limits of your vehicle's traction and handling. The systems in a normal passenger vehicle can be intrusive for even a moderately decent driver, and in some cases can be a hindrance.
 

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mpd8488 said:
ABS is not designed to shorten stopping distances, though it does shorten distances compared to wheel lockup, it is designed to maintain steering control. ABS in a standard passenger vehicle only uses about 75% of the vehicles braking ability, while threshold braking can allow you to utilize over 90% of the cars abilities. It is better to be able to steer around an object in an emergency, even if it means compromises the braking distance just a bit.

The traction control systems in high end performance vehicles and racecars are going to be completely different than you standard sedan or SUV. The sytems in a corvette or a porsche, for example, might only engage when the computers sense that you are just about to cross the limits of your traction, while a system in a car won't let you get anywhere near the limits of your vehicle's traction and handling. The systems in a normal passenger vehicle can be intrusive for even a moderately decent driver, and in some cases can be a hindrance.
You are technically correct in that the primary goal of ABS is to allow steering input while braking, however you are quite incorrect about its effect on braking distance compared to threshhold braking. ABS straight line stopping distance is shorther than any human can achieve using threshold braking, period. Look at the difference for professionally driven test cars with and without ABS when ABS was first produced, you can still see those numbers posted on cars that ABS continues to be optional on, and professional test drivers still ALWAYS get significantly shorter numbers with ABS, period, saying anything else is just wrong. You see ABS is computer controlled threshold braking, it uses far more of the cars braking potential than even a professional driver can possibly muster, because it reacts MUCH faster than even the best driver. Bottom line a human can NOT match ABS stopping numbers even in a straight line compared to the same chassis without ABS. The ability of a human lags farther and farther behind ABS the more steering input is applied during braking. Lets look at ABS in super high performance cars. The Enzo, CGT and SLR are three of the highest performance street cars ever sold, they all cost over $400K, they all have ABS and none of them have an ABS defeat switch, why, because even the best track junkie would never switch it off. They all three have traction/stability control defeat buttons, why, because the very best track junkies can use increased slip angles and throttle steering to get around the track faster and/or with more "style". Trust me if ABS made those cars faster around the track, there would be a ABS defeat. A further indication that ABS is better than humans is the fact that it is banned in so many racing series, guess why, it would make less capable drivers faster because it is just better than the best humans at using the most braking potential on a chassis. Again your 75% vs 90% is so far off it is funny. Now there are even more enhancements to ABS in higher line cars. EBD for example. Electronic force distribution moves braking force away from tires with less grip and adds it to tires with more grip, again coming closer to the mythical 100% braking efficiency, try that with one pedal and no ABS, just another example of how computer controlled ABS adds another advantage over a uman using threshold braking and moves the effiacacy closer to 100%. Add to this innovation is brake assist, in cars so equipped, it adds braking force if it feels you are executing a panic stop, some cars add a system that if you come off the accelerator pedal quickly, it anticipates you may be planning to panic stop and preloads the braking system pressure so that in the event you do hammer the brakes the pistons will reach full presssure faster. Bottom line a human can NOT match ABS for safe, predicatable stopping distances with or without steering input and you will not find any credible evidence to support the opposite position.

I did make the distinction between high performance and more pedestrian traction control systems. The bottom line here is if you engage traction control on the street with even the most restrictive systems you are either in a panic maneuver situation where the chances are 90% or higher it will be a positive for even the best drivers or you are intentionally pushing the limits of the vehicle which has no place on the street! Traction/stability control systems should have defeat buttons for track or off road use. I have a friend that is a driving instructor at the BMW performance center, whose racing background is rally (rally drivers are known to have the best car control) and he never defeats traction control on the street, because he knows better.

This debate is like the seat belt debate, it is finally dying out (thank goodness) but all of those who refused to wear them and felt they were unsafe were speaking anecdotally and not statistically. No amount of practice or training will allow a human to better a properly operating ABS system, only the very best drivers (professionals and drivers that spend 20+ days a year on the track) are going to be faster or safer without traction control, and that requires them to be 100% focused on the street just like on the track, unfortunately no human is capable of this all the time.

Now, my proclaimation about ABS vs non-ABS is incorrect on a very limited number of surfaces, none of these are found with any regularity on the road. Anyone know what these are?
 

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Now, my proclaimation about ABS vs non-ABS is incorrect on a very limited number of surfaces, none of these are found with any regularity on the road. Anyone know what these are?
I have always heard that ABS is a hinderance on surfaces like loose dirt, fine gravel, and sand because they tend to roll under the wheels like tiny ball bearings when you hit the brakes. When you try to stop with ABS, the lock-up threshold is so low that the ABS keeps the vehicle rolling for an extreemly long time. If you don't have ABS, the tires will immediately begin to dig in, pushing the dirt, sand, or gravel into a little mound in front of each tire, which very quickly slows down the vehicle. I know that my own experience seems to confirm this, but I've never checked it under scientific conditions.
 

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Check out this site, it does a great job of explaining braking. Take notice of what it says about threshold braking:

http://www.safespeed.org.uk/braking.html

Clearly you have a better understanding of the modern systems than I do, and ABS has probably gotten better by leaps and bounds, and these days the distances differences might be negligible, but certainly not in older vehicles. I will stand by what I said in terms of threshold braking vs. ABS. I am not trying to discredit ABS, two of my three vehicle are equiped with it, but threshold braking can still be used with ABS. You mentioned driver focus and attention, which is a very important point, and why I buy vehicles with ABS. The lack of focus that drivers have on the road is what puts people into emergency situations in the first place.

As for your question at the end of the post, in gravel and very deep snow it might be better to lock the wheels up because it builds a mass of material in front of the tires, further helping to decrease momentum.

This might not be a problem in newer ABS systems, but on very slick ice, for example, it is very easy to lock up all four wheels in the same instant, which can throw off the sytems and allow all four tires to remain locked up.
 

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Ramblin Wreck said:
I have always heard that ABS is a hinderance on surfaces like loose dirt, fine gravel, and sand because they tend to roll under the wheels like tiny ball bearings when you hit the brakes. When you try to stop with ABS, the lock-up threshold is so low that the ABS keeps the vehicle rolling for an extreemly long time. If you don't have ABS, the tires will immediately begin to dig in, pushing the dirt, sand, or gravel into a little mound in front of each tire, which very quickly slows down the vehicle. I know that my own experience seems to confirm this, but I've never checked it under scientific conditions.

That is exactly right, the key is there must be enough material to "dam up" in front of the tires. This can even happen with the correct consitency of snow, assuming it is deep enough.
 

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wow...this has been one of the most educational and interesting threads I've seen. I love it.

Now I bring into question the statement earlier that A-TRAC is the same as the TRAC system. It still makes more sense to me that A TRAC is a name for AWD. Why wouldn't the button just say "TRAC" if that's all it was.

What about this possibility...What if the FJC works the opposite of the 4runner. Meaning that when I select 4x4 in the Runner it is AWD until I tell it otherwise and lock a diff. Because the 4runner is designed 1st as a highway vehicle and 2nd as an offroad. The FJC is 1st and offroad and 2nd a highway vehicle. So when I select 4x4 it might go to 4wd until I tell it otherwise and push A-Trac. plausible? Or does that just sound stupid?

It seems to me that this explination would allow the system to function like the Tacoma's (which is what most of us have thought) but also include the "full time 4wd or awd" mode as we've been told.
 

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mpd8488 said:
Check out this site, it does a great job of explaining braking. Take notice of what it says about threshold braking:

http://www.safespeed.org.uk/braking.html

Clearly you have a better understanding of the modern systems than I do, and ABS has probably gotten better by leaps and bounds, and these days the distances differences might be negligible, but certainly not in older vehicles. I will stand by what I said in terms of threshold braking vs. ABS. I am not trying to discredit ABS, two of my three vehicle are equiped with it, but threshold braking can still be used with ABS. You mentioned driver focus and attention, which is a very important point, and why I buy vehicles with ABS. The lack of focus that drivers have on the road is what puts people into emergency situations in the first place.

As for your question at the end of the post, in gravel and very deep snow it might be better to lock the wheels up because it builds a mass of material in front of the tires, further helping to decrease momentum.

This might not be a problem in newer ABS systems, but on very slick ice, for example, it is very easy to lock up all four wheels in the same instant, which can throw off the sytems and allow all four tires to remain locked up.

I think we are getting closer BUT let me make the point that should make it clear ABS will result in faster stopping than a non-ABS equipped chassis (excluding the rare instances we have discussed such as gravel).

The definition of threshold braking is applying brake force just shy of producing lock up.

ABS systems do NOT intervene until the tire actually locks up.

Given those two facts if you are a threshold braking god you will NEVER cause ABS to kick in... so you can merrily practice threshold braking in any ABS car and it will only step in if YOU screw up and lock the tire. This makes it impossible to argue an ABS car is inferior in stopping to a non-ABS car... :) If you think about this it becomes clear.

I have never read a single journal article nor mass market magazine article that said anything other than ABS produced superior stopping distances. Even the very first ABS systems consistently test better than professional drivers were able to produce. You are entitled to your opinion but in this case the empirical data is completely one sided and not in your favor.

Not sure where you live but if you would like to make a friendly wager, I can arrange the closed track time and we can test your theory using the same car, I brake with ABS and you brake in the same car with the ABS fuse pulled (results in a standard braking system). In the end it is a sucker bet since the fact is no one can out brake an ABS system in the same car. Professional test drivers average 10-20 feet longer, and they do it for a living!


Now I have made a lot of fuss about this since I believe your statements to be who heartedly wrong in the real world and potentially causing problems for people who might listen to them, but there is a catch to this. It is a little thing called the retardation point. This is a point just shy of lock-up and is the magic braking zone, depending on the "tune" of the ABS the system often sees this as lock-up and pulses. So in theory you are correct, however the journal articles I have read determined this point is so razor thin in terms of pedal pressure that race drivers were only able to be on the retardation point less than 10% of a controlled straight line stop.

ABS will beat a professional driver 99 out of 100 times on dry perfect pavement, 9,999 times in the wet or imperfect pavement, ABS with EBD and brake assist with beat a professional driver 100% of the time in any condition save the exceptions discussed earlier in the thread. Bottom line properly functioning ABS and traction/stability control are indeed better at driving than we are... :) There are some Ludites that will argue to the cows come home but this argument will eventually die like the seatbelt argument.
 
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