ABS on this truck is dangerous...

How would ABS stop you from " sliding your truck out " ? That would be VSC

 

I have never really thought one way or another about ABS. Driving for 25 years and adapting to ever changing automotive technology I choose to get the fuck over it.

 

Thats why I quoted FSM (as Factory Service Manual)
As it says there, EBD is part of ABS unit.

How than?
you need brake distribution not only when you slip but during normal braking too. So how would system know how much force to apply to wheels just by looking at speed sensors ?

If I ask you to figure out how much force you need to stop feather falling in vacuum. and how much force you need to stop bowling ball falling in vacum just by looking at their speed , how would you do it ?

 

There are more sensors involved than just wheel speed to make brake proportion control reacting to weight distribution to work. I'd have to look up how it's accomplished, but it could be done by load/pressure transducer at the top of the suspension mount on the Prius or car

 

Slam on your brakes, jamb the wheel left or right. Does it slide sideways or turn sideways?





Hint....it turns, unless your doing 80 mph, then that would just be a dumb thing to do.

This

 

When (if) you panic stop it releases the brakes and allows the wheels to continue rotating. That's f'd up.

 

Ploughing > ABS for stopping on snow

 

It is supposed to decrease enough brake pressure to release the wheels from a 'locked up', not moving state then increase pressure again, until they start to lock again. Locked up wheels slide further, and cannot offer steering control.

It was originally designed for aircraft for the same reasons.

Modulating the brake pressure maximizes the braking power available without locking up the wheels giving you control and should minimize your stopping distance. Problem with pre 2011 Tacoma, is it seem it does not disengage this cyclic operation at low speeds, such as more modern systems, post 2011 Tacoma do.

It is still up to the driver to drive within the physical limits of the road conditions, as ultimately the amount of friction available between the small contact patch of your tire, and the immediate surface is the only friction available to stop. Exceed that, and nothing is going to help.

 

True, when snow is deep enough, or in slush.
So is running into a curb, ditch or snow bank. That will stop you, and sometimes is the best alternative.

 

I kinda always ignored this thread but after last weekend I truly believe the ABS to be dangerous.

So it snowed heavy christmas eve. The snow plows were not up and running on the little streets. The cars were still driving on the roads and compacting the snow. Christmas was cold and the snow turned to ice. I made this same turn multiple times on both those days. The next morning however I was in 4hi chatting with my wife driving slow and safe. I started to make the right turn. Almost a U turn onto the street my inlaws live on. The snow had still not been plowed. The road I was on had slush but the road I was turning onto was a sheet of ICE.


The turn is the purple pin



Photos of the turn the next day saturday.


Looks liek some one did the same thing saturday


I started the turn like normal but the truck quickly decided to ignore my turning and braking. Even though I was going slow I hit a post (an older post) that was rotted on the bottom and broke upon contact with my relentless bumper. We started going over the edge and I thought for a moment. This is it.



The cable had been cut when they replaced the two new posts on the end and instead of sinking a new cable in the ground they Ubolted the two cabels pieces together. This did not hold so the post just fell over. The saving grace was my truck was completely sideways and I hit a new post on the side of my truck that held us in place.







I was looking over the edge in shock. It happed so slow it felt unreal. Like this cant be happening. The ABS brake system would not let the tires stop and the truck was just letting off the brakes at around 2 miles an hour there was nothing I could do. The truck was sliding almost sideways down the hill. In hind sight I could have shifted into low or engaged the parking brake but It didnt feel real. If felt Like I should stop at any moment.

My wife quickly snapped me in gear and said what do we need to do. I handed her my phone and said take pictures Ill grab the recovery gear. I couldnt back up because the post was resting agianst the side of my truck. I ran the winch to a tree across the road but this did not work as the back end if the truck started going down the hill while the front went up. I grabed the snatch block given to me by my TW secret santa and ran the cable back to my slider. Once I was off the post. I had the wife spin the wheel in reverse while I winched sideways. This seemed to have the best result.



The good news is we were safe. My $250 diductible is nothing and the body will be fixed. I had to make the same turn several more times this weekend. What did I learn? 40 PSI is too high. A nice 30 in the mountains helps. Using my gears to brake gives me much more control. It was an experiance that will be with me for a long time.

 

Bingo

Snow type / depth / moisture content plays a huge role

 

That sucks

 

Great job on the self recovery Nick!

Thats what our rural roads look like in the winter, usually with less pavement showing. Temperatures at or just below freezing are the worst, because the little friction you do generate causes heat at the surface point of contact, and you glide on film of water/ice.

Managing those driving conditions is done entirely by limiting the vehicle speed at the start/top of the hill with a low gear, brake on the straight sections only if you have to, and use no brakes at all in the corner. Pretty freaky feeling once it does slide, and there is nothing you can do to stop it.

Edit: on cars a small application of that handbrake handle can create enough oversteer to point you around the corner. On our trucks that is difficult to control properly because of how the e.brake releases damn it.

 

Glad you didn't go over that bank.... That woulda made some scratches that you couldn't "buff" out...


What kind of tires you got?.... They look like off road or mud tires....Pressure might be an issue too ?? (They are way harder material than snows and do not grip ice or snow very well...)


Glad it stayed a "minor" accident... That's one hellofa corner at the best of times.

 

That sucks, but I can almost guarantee you that if you didnt have ABS you would have hit that post alot harder than you did with ABS and very well could have gone through and over the edge.

Like VE70SR said. It doesnt turn the braking off like there is no braking at all, it merely takes enough pressure off to get them rolling again while still exerting as much pressure to the brakes with out skidding, this is why the brake pedal bounces.

ABS has saved my ass more times than I can count.

 

Actually it's a fact that ABS increases stopping distances on low traction surfaces

 

I was pretty bummed. I do think its funny all the crazy stuff Ive doe in this truck and the first real body damage happens on the road.

It was 18 degrees when I slid off the road. Ive slid on Ice before but never like this . I just kept going.

I have Hankook Dynapro MTs. They have done well in the the mud, sand, and snow but now I know they suck on ICE.

Its pretty much a downhill U turn but I wasnt ready for the change in road conditions. I was going slow but just wasnt aware of what could happen and how serious I should have been taking the road conditions.

 

More than going into a full on skid? I'm dubious.

I was driving through San Francisco in a non ABS truck when a stupid chic decided to slam on her brakes to make a left, I slammed on mine and the truck actually felt like it accelerated right into the back of her. The exact same thing happened in the exact same condition in my Expedition and the ABS kicked in and no harm done. It was raining, wet road, both times.

I'll take my chances with ABS.

 

wut? as compared to locked up brakes? actually that does make some sense, but it is not universal and is dependant on temperature, and road surface conditions. For most less than average drivers it saves their butts in panic situations because you receive some modicom of steering control, perhaps at the expense of stopping distance.

 

Im pretty sure I would have stopped sooner if it locked up.