Disable ABS for Winter Driving

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

"Even dirtbikers gear down and come off the throttle on loose gravel/rock as they enter a corner because ANY other braking is too much risk"

Come on, 1.5" knobby tires with 400# is a different world than all season tires and 6000# all on gravel or snow. Most riders are down shifting before the corner to get back in the powerband while exiting the turn as fast as possible.

Doug please correct me if I an wrong;)

Every tire in any condition has a finite amount of traction. That traction can be divided between steering, braking or acceleration. Once you surpass the finite amount of traction you are skidding. Sometimes controlled (formula one, rally...) and sometimes not so controlled (careening on ice into the a ditch). ABS is a good thing. 4 Channel ABS allows the maximum traction to be realized at each wheel in any condition for steering or braking based on the systems cycle time.

But, ABS is limited to the number of cycles the system can perform per a unit of time. This is why expert driver in a controlled situation can can beat the system in stop distance. If the ABS cycle time was fast enough it would beat the expert driver every time.

"Threshold braking allows you to brake using maximum friction on your brakes without causing the brakes to lock." Wrong.

Threshold braking will not allow the driver to control and/or modulate the maximum amount of traction at each individal tire. 4 channel ABS can.

Fact is with 6000# of SUV, 4 channel ABS is a great thing. Trying to control 6000# in a SUV with a high C.G. is stupid (sometime fun in a parking lot). As an experiment, try jamming the steering wheel to the right or left on that gravel or snowy road down hill while threshold braking. After, can I have dibs on your locker thirds? :grinpimp:

Landy, you have no mechanical enpathy. Dropping an auto into a lower gear to gain traction is dumb and distructive.
 
Doug, I've read enough of your posts to know you are credible and have qualified background experience - I appreciate that. This alone is enough for me to re-think about why I thought I could stop sooner W/O ABS. Im glad you agree with threshold braking. The secret is to find the threshold - ABS is invented to do the panic thinking/reaction needed to stop in a timely manner. But there is absolutely no doubt, from one experience I had where ABS let me down. I tried it again with ABS off for interest's sake and I stopped 25' sooner (on ice and compact snow) than before.

But I feel I need to be clearer on the downshifting thing. Downshifting should be the last thing on your mind in an emergency where you have to stop NOW. I want to be clear on that. However, seeing something ahead that would cause you to want to slow down in a controlled fashion might cause you to down shift to, say, 3rd from OD when doing 50MPH. Dropping it into 2nd at this speed would be suicidal and killer on your engine and trans. The next time Im on the main Forestry Service Road (where there is presently snow) Im going to take a few minutes to perform some unscientific tests for fun - just for self edification. I really want to rethink my ABS experience from last time.

Cattledog, I don't know what enpathy means, but I think I'm getting the gist of what you're saying, and you're wrong.

Good dialogue

Cheers.
 
Landy, where am I wrong?

Down shifting before the corner to get in the powerband on a two stroke bike?

4 Channel ABS's ablity to manage braking and steering traction to each individual tire better than a driver with one brake petal?

The idea that dropping the tranny into a lower gear looking for more traction on slick conditions being hard on the drivetrain? Thats how I read you earlier posts. Shock loading an auto tranny is a bad idea.

Keeping factory ABS on while driving a 6000# SUV with a high C.G to maintain conrtol in low traction conditions?

Please explain.
 
Gentlemen,
Again, I am not trying to agitate an already/clearly emotional and heated debate. However, a ten second search revealed this on Google. Please read the Overview for the pertinent information. I put this up not to agree or disagree with anyone.........just as information. http://www.freescale.com/files/shared/doc/selector_guide/SG2006.pdf
Now, as far as what is the 'best' that is clearly a judgement call. Nobody can convince anyone who has already made their mind up.......ON ANYTHING. My point however is this. It appears to me that in the short time I have been lurking on this forum there is a common and troubling vein that threads tend to fall into. Without actually attacking one another, people become........let's say PASSIVE AGGRESSIVE. This causes people to behave in a counterproductive manner. Most of us are here because we ARE ignorant, but there are ways to say things, and other ways which serve absolutely no purpose whatsoever (those of you know what I speak of). So I ask, as a favor for those of us ignorant fools, you refrain from uneccessary derogatory remarks. Really, does it actually make you feel any better??
Now I have nothing but the utmost respect for Doug and what he brings to this forum. I value him as a great resource, and pretty much re/re-read ALL of his post's. So know this is not directed at you.

CANT WE ALL JUST BE FRIENDS??

My .02

Chris

94 FZJ80 139K 2.5 OME CDL Pin 7 285's DD
 
Last edited:
Well I can say I gave my ABS and t-case a workout driving home today in 3 inches of fresh, wet snow.

With the benefit of my "Pin 7 Mod" (Thanks, CDan!) I tried some A-B comparisons, with the t-case in open (ABS on) and locked (ABS off) modes. (Aside: This is not a true A-B with a locked t-case since the front to rear proportioning is in effect disabled. We'll ignore that for now.)

With ABS on the truck stayed straight and very "steerable" around curves. I will add that after I pick up my daughter from day care I did slide down the driveway on a slight downgrade into the road. I was braking with the ABS cycling ... but not stopping. Luckily this is a back road with very little traffic and no one was coming. This was not fun but something you need to be aware of driving with ABS.

With ABS off as I applied the brakes and locked the wheels the truck started to slide sideways due to road camber. As I lifted the brake pedal the wheels would start to roll again and the truck would jerk back on track.

Overall, the truck is much more controllable, stable and steerable with ABS, albeit with longer stopping distances during very slick conditions. I would not recommend to anyone to disable ABS during winter traveling.

Desert running in is a different story.
 
keep the abs and lose the michelins , had these on a suburban and a toy 4runner, suck in the snow and rain, look at the tread they tend to look like they have alot of tread but tend to get rock hard and feel smooth almost glazed over causing them to be slippery and in turn the abs come on, traction and tires play a big part in how the abs works , i am looking at a land criuser right now and if i buy those tires will be the first things changed, just my 2cents worth
 
Im glad that 1 other person and the PDF file on ABS supports my own finding that ABS increases stopping distance in snow, at least Im not going insane. No doubt ABS allows you to maintain much more control in steering than without. Doing evasive manoeuvers w/o abs will cause wheels to lock/unlock at will due to shifting weight - something mentioned before.

You are not shock loading going from OD to 3rd doing 50 MPH. No-one would be downshifting on a mountain road or while towing a trailer down a grade if trannies were dieing left and right.

BTW, my own experience with ABS was when we got a sudden dump of snow. Doing 25 MPH the light changed, and my decision was to stop. I slid to the middle of the intersection with ABS pulsing. Since it was early AM in my small town I decided to do a trial to see what I'd do w/o ABS on. I hit the brakes with ABS off, not locking them (not downshifting though). I stopped around 6 feet before the white line. I was honestly shocked. However, performing evasive manourvers, like in a real emergency, so many variables are at play that ABS's design is to "think" for you while you focus on steering. This is why I'd leave it on. Rarely do people just stop. They stop while steering.

The thing that complicates this discussion is the fact that if your CDL is on, your front and rear diffs are locked together - they turn at the same speed. So if your front wheels wanna lock they might not because the rear ones want to turn, and vice versa.


Mr. Salty, we are all friends, its just some people express their love in different ways;). Besides, as Uncle Red from Red Green says, "we're all in this together...", 80's that is.

Cheers
 
You must log in or register to reply here.

Share this page

Back
Top Bottom