How does ABS go offroad?

[its fishi]

Having never had a 4wd with ABS before can any of you knowlegable types let me know what it's like when rock crawling etc.

I'm wondering if it releases the wheel to spin just when you don't want it to. e.g. descending sandstone steps when there's a bit of loose sand on the surface and you are kind of sliding/skidding a little then coming to a halt.

it's a NH SWB

thanks

[Glennb]

Im not an expert and dont have ABS but I would think your rear brakes would still help you stop as they dont have abs and if they are still slidding I guess you would still slide with or without abs if your on something slippery.
And come to think of it my abs on my ford would not work unless I was doing more than 40kmph.It could be the same for you car.

[DougH]

To the best of my knowledge these trucks have four channel ABS.

There was a trip report by a fellow named DougM way back when in the 4x4wire forums. He reported that the abs activated and caused him to brake very poorly down a hill. If I remember correctly he was pulling the fuse for the ABS after the incident for offroad use.

[its fishi]

Yeah I would have thought it would be at least 3 channel, but have not crawled under to check.

Pulling the fuse was my back up plan DougH.

[Zute]

Ive read, that if you modulate the brake pedal ( press and release quickly several times) it can work abit like traction control.

The spinning wheel gets the brake power, the wheel with grip gets the drive. you need to left foot brake, because you need to keep the power on at the same time. Would be easyer in a Auto.


Never tryed this myself as I dont have ABS. So if any one does, please try, and let me know if it works.

[DougH]

I thought that is what lockers are for.

[glenn_c]

You can use your hand brake to help your LSD work better.

[M1S3RY]

Mine has ABS and when i get a lot of wheel spin and bouncing the warning light comes on and the brakes seem to work very poorly especially when on a hill..

[its fishi]

Mine has ABS and when i get a lot of wheel spin and bouncing the warning light comes on and the brakes seem to work very poorly especially when on a hill..

M1S3RY, do you mean when picking your way down a steep bit? would you happen to ahve a facotry locker installed?

[M1S3RY]

Mine has ABS and when i get a lot of wheel spin and bouncing the warning light comes on and the brakes seem to work very poorly especially when on a hill..

M1S3RY, do you mean when picking your way down a steep bit? would you happen to ahve a facotry locker installed?

Happens when going up hill with locker, slidding and bouncing around trying to get some grip. Then once your stuck and need to hit the brakes, braking is like braking when you have to car turned off, not very good.

[Grantw]

I installed a switch to turn the ABS on and off.. In the slippery stuff it caused all sorts of excitement....

[Glennb]

They wernt thinking too hard when they installed abs on a 4WD. I woulda thoght they would of have it turn on after a certain speed as it cauld cause problems when 4wding at low speeds.
I bloody hit a car cause of my abs (on ford) at low speed. If I had no abs I believe the car would of pulled up alot quicker.

[Ian Sharpe]

Correct me if I'm wrong,

Doesnt the ABS turn off when 4wd low is selected??

It should, IMO

[its fishi]

Only one way to find out.

[DougH]

I installed a switch to turn the ABS on and off.. In the slippery stuff it caused all sorts of excitement....

Any tips on how to install said switch?

[-Scott-]

I don't know about low range, but it operates right down to crawling speed in high range. A friend of mine with NH shorty and ABS tried to reverse parallel park on a gravel strewn road, nose up hill. When he hit the brakes to stop, the ABS kicked in and the car kept rolling back. He had to use the handbrake to stop the vehicle.

Most people hook a switch in line with the fuse to the ABS computer. Effectively the same as removing the fuse, just a little easier.

Scott

[Bitsamissin]

No unfortunately the Jabber ABS does not switch off in low range.
Some guys fit a dash switch to render it inoperable for offroad.

[EPTiSO]

HI
In my NP 03 I have found that when in 4HLC the ABS is working and will assist in down hill as it stops the wheels locking up . But when I'm in 4LLC the ABS is disable by the computer and it drives like a normal 4WD. The traction controll is the thing i find is the most decieving but it does allow me to get to places that most locked diff 4bes will get to.

[DougH]

Can any one elaborate on this switch to disable to abs? I may just pull the fuse permanently, I am not a big fan of abs. I can pump my brakes just fine.

[Firegod]

ABS and EBDS, (Electronic Brake Distribution System), is nice off road. Still locks up on loose/slippery stuff but to a lesser extent.

Found that if you are not getting power to ground and tap on the the breaks can help. I suppose it sees one wheel as no traction and starts working the other side, or with EBDS, other wheels wanting to work that have traction.

[Grantw]

ABS in mud = (try it and find out) brown dacks

[hongkonger]

On models where a factory rear locker was an option, there is an alternative method. Rig up a relay to advise the ecu that the factory rear locker is operating, which automatically disables the ABS system without the risk of pulling fuses.

edit: Incidentally, I havent done it myself (yet) still at the researching, but according to the manual bits I have read should work without problems, the ABS light will be lite as a reminder to switch it off for on-road driving.

cheers,
John

[Bitsamissin]

Dougie, check the Trail Talk archives DougM did this mod and if I remember correctly if you pull the fuse you have to go through a procedure for the ABS ECU to re-learn. It was something like - turn off ignition, replace fuse, start ignition otherwise the ABS light will stay on like there is a fault. There was much discussion on how to jury rig a bypass and relay to a dash switch to turn it on or off in any situation without having to go through the ECU re-learn procedure.

[its fishi]

hmm interesting hongkonger, thanks for the diagram.

Bitsamissin, wouldn't it be wise to only remove the fuse when the ignition is off anyway?

[Bitsamissin]

Of course, but some had tried just pulling the fuse (motor running) and found the ABS light stayed on constantly.

[hongkonger]

If you pull abs fuses while the ignition is live you run the risk busting the ecu., here is a link:

http://www.pocuk.com/forums/viewtopic.php?t=27845

cheers,
John

[Firegod]

Back out to Appin on the weekend, (hello to those two Toyos dissapearing up the ridge, fine if you got diff-locks and tyres that big)...

ABS down hill was good, the Triton has a real slow crawl in 4H anyway, (can get out, have smoke and hop back in before its gets 2 far away in 4L), while I usually just float down sitting on the gears without braking, it could be bad habbits forming. I'd sooner not use them if I can help it.

Didn't have enough mud to see what happens in that respect.