ABS on corrugations

Correct, the system is rendered inoperative

Wow, I was hoping you wouldn't say that. Has incredibly stupid of you.

I have done extensive testing of ABS systems as a professional driver. In fact, our team managed to break the original Holden Commodore ABS system and Holden re-engineered as a result.

Where ABS is truly shines is on broken or wet surfaces and gravel. In a non ABS vehicle I can brake in a shorter distance than an ABS equipped vehicle BUT only on a good, dry surface. In all other scenarios, an ABS equiped vehicle is far superior and will brake to a stop in a shorter distance.

By disabling your ABS you are a danger to yourself, your passengers and other road users. I only wish I had some way of reporting your behaviour to the authorities but being anonymous on here prevents that.

I don't get it. My car does not have ABS - does that make me 'a danger to myself, my passengers and other road users'. How can it be applied to one car and not to another.

Some car manufacturers bring out a switch to disable the ABS like when the 4x4 is activated for 'off road' conditions. So again - how does that make it more dangerous when manufacturers are implicitly acknowledging the problems with ABS for off road conditions.

Older ABS system were a pox on gravel, at least where braking is aided by building up and pushing a mound ahead of the wheels.

Newer systems are sposed to be better but an acquaintance who's a suspension expert disables the ABS on his Impreza when he goes onto dirt.

I have never had a problem with my braking on corrugations, either towing or not. The ABS works like it should. On the hard stuff during driver training I was able to stop better with the ABS turned off, on a straight drive that is, but put one side on some dirt and it was a different thing again. Same when turning, if you need to brake suddenly the ABS does its job. If his ABS are causing such problems I would get the vehicle checked out. Kevin

The ABS has been checked as has the entire brake system & has been found to be working in accordance with the original settings.
I have driven current vehicles with ABS on the dirt & they are markedly better than my 1997 vehicle.
I have also driven not so long ago an ABS equipped vehicle on dirt in competition with the ABS disconnected . To the best of my knowledge none of my competitors with ABS in their vehicles had it operative.
Myself & four friends who average nearly fifty years of driving experience ( four of us have had quite considerable competition experience on dirt) with similar aged/type vehicles have all tested & come to the same conclusion that with our vehicles on loose gravel/corrugations ABS is best left inoperative .Hard dirt/highway is fine with ABS.
By the way my vehicle has a switch to turn the ABS system off. I believe it is original.
Cheers
Batsy

Ah Dmax...such a silly and thoughtless way of responding to Batsy's topic.....don't 'professional drivers' need to demonstrate common courtesy toward others ? As for Batsy being anonymous...who are you ?

Mr Dmax, a question if I may.
Considering that your good self is a professional driver and expert on all things ABS, and going by your statement that you are capable of bringing a non ABS equipped, or if so equipped, disabled, ABS system vehicle to a more controlled stop on a good dry surface than with the ABS enabled, is it your hypothesis that ABS could result in a collision whereas a non ABS could have avoided said collision?
Considering that the far greater part of driving in countries such as Australia is done on bitumen, which in most cases could be classified as a good surface, should we, the non professional drivers have the ABS disabling function connected to the windscreen wiper operating system so that when the road is nice and dry the ABS does not operate.
Further, should a vehicle also have a driver sellectable switch for use on the surface types as well as the windscreen wiper ABS disabling feature?
Batsy, the OP, by his experience states that he is capable of bringing his vehicle to a more controlled stop with ABS disabled than with it in operation, but without having driven his vehicle in any conditions, let alone on the gravel surfaces he is talking about, you want, not only to come onto a public forum and call him stupid, (your word) but indicate that it is your wish to report him to some authority.
Going by the impression your reply has created in my mind is that you just may have to learn the fine art of getting your point across without stabbing someone with it.
It is called tact.

Cheers
Pop

I think a lot of this comes down to the adequacy of the braking systems and the performance of the ABS.

Some vehicle manufacturers have had difficulty in manufacturing braking systems that behave well.....some of the american derived vehicles have had shocking braking systems....braking systems that simply do not stop straight or without wheels locking up prematurely

These designers of poor braking systems love ABS, because it can make poorly designed brakng systems behave tolerably well in normal driving.......but these vehicles are very much dependent on the ABS to stop at all well.

Then there are some of the early ABS braking systems....often on the vehicles mentioned above......that have fundamentally poorly designed braking systems...some of these ABS systems where very intrusive and behaved poorly indeed on rough surfaces.

In fact there where early ABS equiped vehicles that stopped poorer than competing vehicles that had no ABS....especially on rough surfaces.

Turn the ABS off on a vehicle with a fundamentally poorly ballanced braking system and you could have a real hand full.

Leave it on and it may not stop well at all on rough surfaces.

A vehicle with a fundamentally well designed braking system will rarely be activating the ABS and wont be depending on it to stop in a civilised manner in most situations.

ALSO a modern well designed ABS system will not make its presence felt except in the most extreem of situstions..and may perform a hepp of a lot better on rough surfaces than many of the earlier examples.


So it is not possible to generaise about ABS systems and rough roads.


The other thing that many dont consider...is that braking is significantly effected by the performance of the suspension ( especialy shockabsorbers) and how the vehicle is loaded or the weight is distributed.

ABS like Vehicle stability controll may be badly effected by poor shockabsorbers, suspension and tyre modifications.

and yes many ..or most 4wds disable ABS and VSC in low range.

cheers

I've owned three 80 series all had ABS, all especially the first (early model 80 series) had appalling ABS operation, really really scary at times.
I didn't disable the function.....but gee I really slowed up when I travelled on loose dirt or corrugations.
Currently on my third 200 series, the ABS operation is a LOT better, but you still have to be cautious on loose dirt (as you should)

Wow dmaxqld, way to make an entrance. I'll also stick my hand up as one who has been incredibly stupid. The 80 and 100 series on loose surfaces (grossly exaggerated when towing) has a mostly inept braking system, and it was considered de rigeur to pull the abs fuse when offroad.
I used to travel for work and also well remember how efficient the first series of commodore abs was on gravel. Opening the door and putting your foot down would have assisted more.
I absolutely adore abs, ebd, eba and anything else, but if you were a professional driver back when this stuff had teething problems -and missed it !- then it is for those whom share the road with you that I weep.

Ron,

Stoping distances rated with a calendar... Single lead shoes on a mini was one of my favourites, in dusty conditions when reversing the brakes would lock up solid, remove wheels and hit drums with a mash hammer to release..... :)

I still do most of my braking in advance of a stop and watch people fly past me, braking at the last moment..

Ron I agree with your "tongue in cheek" comments but in reality it's what we had & we were bloody glad to have it.... better than dad's Ford Desoto.
By the way I understand that many of the newer cars now don't even have an ignition key hole....great thing actually as it's real hard to get your key in the ignition switch when you are "legless". HoHo
Cheers
Batsy

Yes we are all expert drivers and or reflexes are much faster then any dump computer...... just because a computer can calculate 1000's of times a second compared to seconds for the average humane brain shouldn't be considered in the equation.

Ron love to put you to the test and see just how quick you can react and outsmart a computer.

About 5 years ago A Current Affair did it with a bunch of young and old drivers who big noted their abilities ...... after the testing all came away thinking different.

Yes expert drivers we all are.... aren't we!

olcoolone, I've been driving for 49 yrs this year, and I've owned a very wide range of vehicles from motorbikes through to a very wide range of cars, utes, 4WD's, and trucks right through to Macks and 100 tonne Drake low loaders.
I reckon I've done well over 3 million kms in that time and experienced every road surface and traffic condition known.

Sorry if I sound like I'm bragging, but I've managed to last this long without having a major accident of any kind, nor have I ever ROLLED a vehicle, or badly damaged a vehicle - of any kind. Nor have I ever injured or killed anyone in a motor vehicle.

Yes, I've had a few bingles - probably the worst was running through a T-junction in the wheatbelt in the early hours of the morning coming home, when I was 18, and when I was tired and distracted.

However, I've had good trainers who taught me how to develop a good FEEL for what my wheels are doing - to ensure that they're always pointed in the right direction and that judicious amounts of power are applied at just the right time.
I was also taught never to panic brake and only apply enough braking to produce a fast stop without wheel lockup. You develop a FEEL through the vehicle, with improved driving skills, as to what the brakes and wheels are doing.

I spent many formative driving years practising my rally-driving style, broadsiding the old Holden utes around gravel bends at speed, to ascertain just where the limits of the ute and myself were.
I was lucky in that respect, few youngsters today get that experience and training.

I don't believe in allowing computers and sensors to take my driving skills away from me - no matter how good the engineers tell me their computers, algorithms and sensors are. Nothing can replace the human brain and muscles when it comes to assessing a situation that requires a quick response that involves mutiple decisions.

I've avoided a woman who did a U-turn directly in front of me with no indication, and without looking.
I nearly hit the kerb on the far side of the road, such was my drastic response - but neither vehicle touched, and neither did I hit anything else.

I want to see the computer that could make the correct decision for collision avoidance, and respond in the way that I did.
I could have just braked, in which case I would have cleaned her up. I chose to swerve, and then correct, and keep up my speed - which goes against many computer programs.

I've had many other nasty squeaks over the years - such as coming face to face on the crest of a hill at 115kmh, with a Landcruiser traytop towing a huge tandem trailer, which was overtaking a bus over double white lines on the far crest of that hill. What would your computerisation have done?

I had milliseconds to decide what to do, to avoid a 220 kmh head-on. I took the right decision, brake hard in a straight line without locking up, and watch the other drivers eyes to see what he was going to do.
He went to my left into the bush, and I squeezed between him and the bus.

No doubt your computerisation would insist that all vehicles must pass on the correct side, and the computerisation would have my vehicle swerving left to initiate a definite head-on at 200kmh.

Nope, I'm sorry, in some relatively rare situations, computerised aids to driving such as ABS can offer a slight advantage - such as reducing wheel lock up on wet, smooth bitumen - but overall, computerisation of vehicle control is all about dumbing down driving skills, and making up for an abysmal lack of vehicle control skills.

There is no way you can say skills or electronic aids are better or worse as every near miss or accident is differant and has so many variables.

The only way you can make a true comparison is in a controlled enviroment.

Not once have I said to my self that near miss would of been better is I did not have X electronic aid in my vehicle.

And computers don't panic and don't make mistakes.....humans do.

I don't think people have lost their ability to drive due to electronic aids...... I think people have lost their ability to drive full stop and you get good and bad in old and young people and vehicles and with and without electrical driving aids.

I am not doubting your abilities but I think you milliseconds statement is a little wrong..... Transistors switch in milliseconds......... 1 millisecond is 1 million of a second. You remind me of the fisherman who caught a fish this size ( ) lol

Thanks CSeaJay. Just spoke to a "tag along tour" operator at the local servo about this subject. He told me he advises those going with him amongst other things to be very careful on loose gravel & corrugated road with their brake distances as ABS doesn't "do everything". Note....he does not recommend disconnecting the system.
He told me of a number of instances where vehicles had had an accident or close encounter & the drivers thought the ABS should have "taken care" of the situation (He smiled at this comment).
Cheers
Batsy

Baz,
you are correct as most trucks and trailers run on bitumen.

They have to make it one size fits all when making it legislation. It will much safer for those trucks that are running bitumen roads. I will just be one of those things others that do a lot of dirt work will have to contend with.

Baz, my take on the legality/insurance aspect is that if the vehicle has an ABS enclosed system (no disablement device included) & it could be proven that the vehicle had the ABS disabled at the time of the incident then the driver/owner would be legally liable & as such the insurance company would most likely dismiss the claim.
However my vehicle has a switch on the dash to turn the CDL on/off & this also does the same to the ABS.
Cheers
Batsy

Big trucks obtain benefit from ABS as air brakes are notorious for a lack of feel when it comes to rapid braking.
Add in multiple sets of wheels which are all difficult to monitor individually through the brake pedal, and ABS therefore offers major advantages for big trucks and semi-trailers.
ABS still doesn't make up for the driving skills (or lack thereof) of the nut behind the wheel.

I had a chat to the tech services dudes at RAA after my first trip away in the Jackeroo when I had a scary experience with ABS on a hard dirt road covered in ball bearing gravel. They said that on some surfaces ABS is worse than useless. We discussed the legality of fitting a switch to disabling it and they said that it could be a reason for the insurance to disallow a claim.

They said that if I really wanted it off ion poor road surfaces, just put a blown fuse in the ABS slot. You wont forget it is off as there will be a warning light on the dash.

Cheers

Now to stop us hitting another vehicle, taking out a cow and destroying a front end, I had a look around (wonderful thing this google).

Link. ABS results on different surfaces.

Yes in a controlled condition a non ABS vehicle can stop in a shorter distance ..... but most accidents are not in controlled conditions plus the drivers reflexes and abilities are different.

For everyday use ABS is great.

BTW ABS was never intended or designed to lessen the stopping distance but to help keep the vehicle in control to steer around and avoid the obstacle.

Thanks for the link, Slow.

George Foessel came out to Brighton Downs some years back, probably late '90's, and put the staff through a 4wd training course. Good bloke, lot of experience and excellent training methods.

Staff reckoned he was good too, as they were able to "fang" around without me getting up them. Did much of the stuff that he mentions in the article, cadence & threshold braking, bit of off road stuff. Even picked up a few skills myself, and no one had to worry about ABS either. :-)

Bob

olcoolone,
what I am saying is that ABS on a corrugated road is down right useless when trying to pull up for an obstacle.

On corrugated dirt roads having no ABS is far better, as for the driving most do ABS is far better.

Yes, ABS was designed so as to be able to steer and brake, but it also has it's down side on dirt and the graphs show it. Controlled or uncontrolled the result will always be the same.

Slow one..... Correct, but people travel greater distances over non corrugated road then corrugated roads.

Corrugated roads bad enough to affect ABS would be in the 0.000000004% for the average driver and then having the need to apply the brakes in an emergency would bring it to 0.00000000000000000006% for the average driver. LoL

Like anything you drive to tne conditions, ones ability and the vehicls ability....... Too many want to find excusses so the don't have to blame themselves.

If I have to hit the brakes hard enough to make ABS dangerous over corrugations then I'm going to fast and it's my fault..... Not the fault of the ABS.

Olcoolone, thanks for the scientific study that shows the percentage that drivers have problems with abs on corrugated roads. LOL.

I don't think anyone is trying to find excuses, at least i'm not. ABS on corrugations is horrible even emergency stopping at 40kph.

Drive to conditions is a phrase used after an incident to cover everything in the automotive world when things go wrong, it shifts blame until they investigate what the real CAUSES were and they can be many, including not driving to the conditions.

On a corrugated dirt road, give me a NON ABS vehicle anytime.

Bob Y,
You are on the money about learning new things. I have done defensive driving courses and I always learnt something that helped me be a better driver. Serious me.


Not so serious me. Others have complimented me by saying I am not hopeless anymore and have moved up to just below average. Not bad hey.

The best thing I ever learnt, was how to get someone in 40 degrees heat to show you how to change that inside tyre, that has wrapped itself around everything after it let go. LOL.

I've also done a few 4wd courses with George Foessel in the 90's when he did our remote area training for AMSA each year.
A smart guy with people skills.
Good to see his results back up what we have all said about abs offroad.
He also backed me up when I killed the diffs in one of our first 100 series in the country (must have been 97 then). They were already giving trouble in the mines too. Of course the upper management suspected silly buggers and were on a witch hunt. It was good to throw it back at them.

Ocoolone
A millsecond is 1/1000 of a second not 1 millionth that is a microsecond. Just in case its important.

cheers

Quick sell it before you loose your driving skills, or do what I'm going to and go to the dealer tommorrow and get all the safety driving aids removed. .....

EO offers a wealth of good advice and information.

Do you think I should get the seat belts removed to?

EO is full of experts in bull bleep .

My point was that very few cars have an ABS disabling switch, yet half of EO seems to be turning it off at will. What, are they all getting out and pulling a fuse? You can disable stability and traction control at will but the ABS still works with those disabled.

Correct - open bonnet and pull fuse.
I haven't done it on any of my last 4 vehicles. (Last 2 automatically switch it off in low range - hint hint)
My current vehicle (ranger) needs traction control switched off manually to go ok in sand.
Current abs is leaps and bounds better than the early stuff.

Mikehzz,

I wouldn't worry too much, as soon as you activate the centre diff lock or engage 4WD in a part time 4WD the ABS turns off. High or low range.

As soon as the drive is 50/50 ABS cannot fully function to give individual wheel braking or safe steering. However as the front an rear are connected the braking is enhanced off road instead of 80/20 its 50/50.

Anyone who has done a 4WD course SISODRV302A or RIIVEH305A or Low Risk SISODRV205A will know this.

If people don't engage 4WD on corrugations or loose surfaces then ABS will do what it does.

In my vehicle, I always lock the centre diff as well as let down tyres and reduce speed on these types of road.

The ABS in my Jeep is still working with the centre diff locked and in low range. I can feel it shudder the brakes quite often especially on rough down hill tracks. That car has no traction control or hill descent either. My Landrover in sand mode, which does lock the centre diff, and with stability control off, a necessity on sand, will still activate the anti lock brakes under some conditions. The ABS kick in is unmistakeable and almost identical in both cars.

I don't know what car you have bludge or what courses you've done, but last I checked abs was connected to the brakes mate, not the driveshafts and I don't know of any mainstream fourby which turns off the abs automatically in high range 4wd unless it can be specifically disabled.

Thanks GBC,

Bear with me a second, ignore ABS for a just a moment.

In high range 4WD, emergency stop foot on clutch, if both front wheels lock up, what happens to the rear, do they turn or lock up?

While the brakes may be on the wheels, those wheels are connected to a prop shaft that when in 4WD is connected to the rear prop shaft and in turn the wheels
If the front prop shaft is not turning the rear one is not turning either.

With ABS on in 4WD ABS would have to release all 4 wheels (3 at least). Resulting in no brakes at all as long as the prop shafts are not rotating.
If the prop shafts are turning one front and one rear will always turn at the same speed, rendering the ABS unable to independently brake each wheel which it is designed for.

In high range 4WD the vehicle relies on slippage to prevent wind up, ABS does not like slippage as it monitors all 4 wheels for traction, lockups and slippage.

If ABS is left on for high range 4WD why take it of just to change to low range? surely ABS high or low range changes nothing? Or what is different or what changes in ABS when travelling at 80 in high range 4WD to 20 in Low range 4WD?

Mikezz with regards to the brake pulsating in high range 4WD.

Quote "Some manufacturers saved the money and did not offer ABS at all on part time 4WD. On some vehicles a warning will flash that ABS is not working properly when in part time 4WD (Mercedes G-Class) - others offer no warning and the familiar pulsating of the brake pedal indicates that ABS is working. Well, its not."

but don't believe me, for a full explanation check here.

Yep, no argument.
The reality however, is a 100 series cruiser towing a trailer on Fraser, leaving Orchid beach and heading on the Wathumba track out past the old Rangers hut.
Casually cruising down the sandy hill and a ranger's ute casually appears around the corner.
Without a word of a lie it took a good 4 to 6 seconds to casually roll down that hill, me with both feet on the brake pedal, and bounce into his bullbar. The abs basically stole my brake pedal. One wheel loses traction, the brakes let the bloody lot go.
Like I said prior, this has been largely rectified on more modern vehicles, but I have first hand experience with having control of a vehicle taken from me in a situation which should never have been so. I also had it happen pulling up the trailer in the rain on tarmac with that same series of vehicles.
Just to confirm, I absolutely love having acronyms (abs, ebd etc etc) but some of the early stuff had pretty big holes in it's cloak of armour.

I don't see an issue. If the diffs are locked, then either both ends of the locked diff will stop rotating and the ABS will release both wheels at the same time, or they won't lock up at all and the ABS will do nothing. It wouldn't be possible for only one end of the locked diff to stop rotating.