ABS and brakes offroad

Andrew I don't have any first hand experience with ABS brakes. As I understand it they allow you better control over steering in an emergency stop, but take it takes the vehicle longer to stop.

Andrew,
What happens is when you slam on the skids on a loose gravel surface with ABS, the ABS kicks in big time to stop the wheels from locking. It does such a good job on loose gravel that the end result is virtually NO vehicle retardation whatsoever. Can be very scary.
By disabling the ABS, in the same situation the wheels lock up and push a bow wave of gravel in front of the tyres, providing SOME stopping power.

ABS works fine on a firm surface and I for one wouldn't buy a car without it. But it can be very scary on dirt.

Thanks guys for the heads-up..........still can't guarantee that he wouldn't have hit the tree though ;-)

Andrew

Quote: == Apparently he had to stop in a big hurry and couldn't. ==

Then maybe he was going to fast for the conditions.

People believe that ABS makes you bulletproof.

NEVER had any problems on dirt/gravel with my ABS . . . EVER.

flappa, I've heard his story from others, and the fact that he's highly experienced offroad makes me think that it might not have been him that caused the problem.
Scenero is easy to imagine, some idiot coming on the wrong side of the track around a blind bend...we've all been there and done that.

I totally agree with Mr Bitchi....... I have installed a simple on/off switch to by-pass my ABS.....simply replaced the fuse with an adaptor, with 2 wires leading to the switch and with an in-line fuse.

The feeling of having NO brakes on loose gravel is BLOODY SCARY!!!!!!

People (who don't know any better) say that without the ABS working you run the risk of locking the wheels up (not a good thing as you lose your ability to steer). I would MUCH rather be the master of my own destiny in this regard, thank you very much!!!!!!!!!

ABS is great on hard-packed surfaces (bitumen, concrete and dirt roads with no gravel).

Quote: == Apparently he had to stop in a big hurry and couldn't. ==

Then maybe he was going to fast for the conditions.

People believe that ABS makes you bulletproof.

NEVER had any problems on dirt/gravel with my ABS . . . EVER.

Couldn't have said it better myself

Baz.

Flappa and Baz...............

Haven't you blokes ever been tootling along at a "safe" speed on a loose gravel road and

1). had a skippy jump out at you?
2). had an idiot come at you around a blind corner, all over YOUR side of the road?
3). come across a large washaway that "shouldn't be there"?

The scenarios are too numerous to list...........basically the question would have to be: haven't you ever had to do a "panic" stop?

Okay, so the operative word in my 1st sentence was "safe". You could travel everywhere at 20k/h and probably never find yourself in a panic-stop situation.

The scariest situation I found myself in was on our 1st Cape York trip. There are all these DIPs in the road. Some wag has added to each "DIP" sign with things like DIP stick; Chilli DIP etc etc.

Anyway, when I first came to a couple of these (they are deep enough to swallow a Kenworth), I slowed right down from 80k/h (what I considered to be a "safe" speed) to about 30k/h. After having done that for the 4 or 5 DIPs, and finding that they were all really smooth, I decided I was being a bit of a wus for slowing down so much.......my "cavalier-level" rose considerably and I decided I didn't need to slow down as much. Imagine the view the inside of my jocks must've had then, as they watched my sphingter valve tighten up quite considerably when I reached the top of the entry point of one of these suckers........about 20 meters above the lowest point......and about an 18" wide x 6" deep wash-away at the bottom.

Anchors away!!!!!!!!!!!

Naught happens!!!!!!!!!!!!!

BANG!!!!!!!!!!!!!!!

Lucky I'm in a Patrol and not one of those namby-pamby independant front end machines!!!!!!!!!!!

Get to the other side. Pull up. No damage (thank crikey). Pull fuse on AB bloody S!!

Make mental note to assume EVERY DIP has a similar washaway at the bottom of it!!!!

;-))

Quote: Haven't you blokes ever been tootling along at a "safe" speed on a loose gravel road and

1). had a skippy jump out at you?
2). had an idiot come at you around a blind corner, all over YOUR side of the road?
3). come across a large washaway that "shouldn't be there"?

The scenarios are too numerous to list...........basically the question would have to be: haven't you ever had to do a "panic" stop?

Yes . . . so what ?

I stopped ?

Still had control over the vehicle , and was able to turn.

What would you prefer ? To have all wheels locked up with NO chance of being able to do anything.

Sorry , I'll take my chances by HAVING my ABS working.

Your call mate.

Ive put a centre diff lock switch in my ABS cruiser, which disables it till next time you shut the ignition down....imagine being on the "marbles" coming up to a tee intersection and the wheels wont skid..they keep a turning....
When it does happen to the rest of you, i hope you have spare undies under the seat.
Andrew

Hey Dozer, According to some of the dudes on here, the likes of you and I are prone to driving beyond the conditions if we have to brake sooooo hard that our ABS causes us any grief. You and I are on the same wave-length I reckon; until you've been there, you can't know what it feels like.....bloody scary chit!!!!!!!!!!

And again i gotta agree with Graeme (flappa) been there done that Roachie with and without ABS, i'll keep my ABS thanks i like to be in control and ABS gives you control, aspecially with the camper on

Baz.

Baz
I got to agree with you too...there is a place and time to disconnect ABS. Legally, it is nowhere...so you have sided on the cautious side...Toyota make their trucks in a way that you cant drive too fast to ever need the ABS...ie disconnected in low range....however, now that i have the switch, i also have brakes on corrigations and marbles.
Andrew

Baz,

with a camper on, you of all people should want to pull the fuse. Unless the camper is electrically braked with a separate controller.
I drive offroad for work in a myriad of hire cars, 4wds etc. An mechanical override trailer will push an abs cruiser down a sand hill with the bakes on as far as you can push them, and the thing will run like it's freewheeling.
A commodore on gravel is similar - even the bloody handbrake is subject to abs!!!

We aren't talking about silly people doing silly things here.. but like the others say - until you've experienced it you won't ever know.

Manufacturers are aware of the shortcomings of this and are trying to do something about it, but offroad I want full control of the brake pedal, and abs takes that away.

Don't get me wrong - abs onroad is great, but it isn't all things to all men (and women).

C.J.

True, but if you can stop in time you don't have the sudden stop at the end :))

Ah yes that's the secret to survival. Go for a walk through any cemetery and listen carefully and see if you can hear the screams from the road accident victims as they tried to stop IN TIME!!

DIO, if you're hearing screams in cemetaries mate, I'd be a bit worried if I were you.

That's not what you're on about , are you.
I suspect that the same could be said for any driving situation that resulted in a fatality.

Don't mind me - seen too many fatalities, young blokes, speed, modified vehicles, thought they were indestructable/bullet proof, most of them COULDN'T STOP IN TIME they paid with their lives THEIR FAMILES ENDURE THE LOSS AND ANGUISH EVERY DAY. Just makes me sick when I hear of yet another driver, wanting to modify their vehicle - in this case disable ABS etc. What ever happened to the tried and tested survival technique when driving i.e. DRIVE WITHIN YOUR CAPABILITIES AND THAT OF THE ROAD AHEAD. Sorry to sound like I'm beating the drum (I AM) too many drivers look upon their vehicles as something to have fun in (whilst on the road). The road is NOT the place to have fun whilst driving.

There said my piece, cleared my chest.

DIO

Don't mind me either. I've lost people in road accidents, as have others on here.
I wasn't having a go, it's still an emotional thing for me and always will be. Sadly I'm not alone. I wouldn't want anyone else to have to suffer.
But the post was about ABS, not my background. I've already said that I know nothing about it, so the debate is informative for me.

Life is all about learning. I like the idea of learning from others mistakes although believe me I've made 1 or 3 myself over 60+ yrs. Try not to make the same one twice though.

spot on steve.

I drove a magna with ABS on gravel at about 30km/h. Hit the brakes and it just kept going and going and going towards a dirt embankment- scared the crap outta me because it wouldnt stop with the ABS chattering away. I went back to the same place and tried it in my 4 tonne cruiser- it pulled up in half the time even with twice the momentum. After that I pretty much refused to drive an ABS car on gravel.

A few years later I drive a 100 series with ABS down a haul road and had to hit the skids for a skippy- It felt like the cruiser pulled up as fast as my non ABS 80- I was well impressed. I dont know if thats the difference in ABS between onroad and offroad vehicles or if thats just where technology got us in those few years but Im still not sold on it. I reckon ABS on gravel sucks compared to cadence braking. On road- well, I'd have seen at least 2 pedestrians cleaned up by city drivers already if it wasnt around. It definately has a place on roads.

Some ABS systems only work for a short stretch of time. If you are going down a long steep hill the abs system may switch it self off and go to sleep till it resets it self. ABS is not very good when doing real tuff stuff off road but I would not be without it on a hard surface and at normal road speed. Sometimes you may want to use accelerator and brake at the same time when 4wding, ABS does not usually like this!

Just thought I'd throw my two bobs worth in. I've had ABS in both work and private cars since the early 90's. On the bitumen ABS is terrific, and an excellent life saving device. I wouldn't be without it. On loose gravel and worse still mud, ABS will actually reduce the braking effort and increase the stopping distance. There have been plenty of comments here about driving too fast., but has anybody making these comments tried driving on wet red clay. It is like driving on ice. Even 20 km/h can be too fast. With ABS, as well as losing all braking, you can lose all steering as well. Under these conditions, the only pedal that provides any real control is the right one. Rob is correct in talking about the threshold method or feathering the brakes, but ABS can make that very difficult. I challenge those who have made comments about driving too fast etc., to drive on a wet gravel road and perform an emergency stop using ABS. Then take the fuse out, and use maximum braking without causing a skid. I'll bet if you've feathered your brakes properly, the stopping distance will be shorter without the ABS.
Keep the shiny side up.
Ferris

==I challenge those who have made comments about driving too fast etc., to drive on a wet gravel road and perform an emergency stop using ABS. Then take the fuse out, and use maximum braking without causing a skid. I'll bet if you've feathered your brakes properly, the stopping distance will be shorter without the ABS.==

I think the alternative viewpoint was that if you just slow down, then the stopping distance will be even shorter still.....ABS or non-ABS.

Not necessarily ideal in all cases, yet it would solve most of the problem.

Andrew

Knowing your vehicle and testing it out under varing conditions , sounds like good advice to me Muddy.

Not all ABS systems are created equal , with some not controlling all wheels but
say rather the back axle as one system.

There are clearly circumstances in which ABS does not work , and a lot more in which it does.

For me I have experienced ABS failure driving friends cars on steep loose hills and I went out of my way to get a car without ABS (manual patrol 4800).

Robin Miller