skidding on black ice

[ericher69]

I'm betting those of you who think they can stop faster without the ABS would find out if they did some exact testing, they would find out they can't stop faster without it. When you find yourself sliding and you don't think the ABS helping, it probably because there isn't any traction available and you are driving to fast. Don't blame the ABS for this. Its happened to me before and I can understand the thinking behind it but its wrong.

It is possible IF you know what you are doing and are proficient at it (I don't pretend to be better than ABS)

ABS is for the masses that just get in their cars and drive.

As a teenager I would purposely go out in foul weather with my fathers '79 F150 and experiment in empty parking lots or streets that had no buildings or traffic on them.

Now my first experience with my '96 silverado in a 4x4 skid made me re-evaluate everything I had learned/practiced. What a hopeless feeling.

I recently experienced this again with my '06 sierra (yes overdriving conditions) and I put the transmission in neutral and made slight steering corrections and was able to stay out of the snow bank.

Our yearly emergency vehicle operations driving training teaches us to put the truck in neutral to significantly reduce breaking distance.

Not saying this is the end all be all but is similar to pushing in the clutch; keep your hand on the shifter to pop back into drive quickly if needed.

Sent from my iPhone 5s 64Gb using TractorByNet

 

[slowzuki]

People have a lot of misunderstandings of 4wd. Those awd's with open diffs and open middle diff drive much better on ice/black ice/freezing rain. A 4wd with no centre diff and even worse one with true lockers in the axles are terrible on ice. The lack of diffs force the tires the slide if you are doing anything but driving straight and on ice that equals less traction for steering and staying on the road.

Once you get into deep snow the true lockup 4wd's are far better of course as all the tires have to turn together.

There are other types of awd as well with computer controlled diffs, viscous lockups etc. Have owned almost every type of 4wd and awd but for driving on ice the basic open centre awd that can technically get stuck with one tire on ice is far better for commuting on ice.

 

[slowzuki]

People have a lot of misunderstandings of 4wd. Those awd's with open diffs and open middle diff drive much better on ice/black ice/freezing rain. A 4wd with no centre diff and even worse one with true lockers in the axles are terrible on ice. The lack of diffs force the tires the slide if you are doing anything but driving straight and on ice that equals less traction for steering and staying on the road.

Once you get into deep snow the true lockup 4wd's are far better of course as all the tires have to turn together.

There are other types of awd as well with computer controlled diffs, viscous lockups etc. Have owned almost every type of 4wd and awd but for driving on ice the basic open centre awd that can technically get stuck with one tire on ice is far better for commuting on ice.

 

[Gator6x4]

Ill wager you wont find a Subaru driver in any of those "displays".
larry

Probably would, if referring to Atlanta. One could have been driving a tank, but when the road becomes clogged with vehicles, there is no where to go. I did see a lot of high dollar all wheel drive vehicles shown on television with people pushing them trying to get them to find traction on the ice.

 

[aczlan]

Probably would, if referring to Atlanta. One could have been driving a tank, but when the road becomes clogged with vehicles, there is no where to go. I did see a lot of high dollar all wheel drive vehicles show on television with people pushing them trying to get them to find traction on the ice.

Yep, and if you have junky worn out all seasons on a Subaru, it will get stuck on ice just as fast as any other vehicle...

Aaron Z

 

[ericher69]

[*]If it is a RWD automatic trans -- find how to drop it to first gear as fast as possible. The drag will generally get you going straight, and slow you down. 2cents:.

Bad advice all around...

1- very dangerous on BLACK ICE as the sudden uncontrolled wheel change speed WILL act like applying the park brake.

2-Probably won't fall into first as automatic transmissions will not fall into a lower gear out of operating limits

3-if it does and you hit a patch of dry pavement it could send you into the rhubarb and destroy your tranny and over rev the engine.

Sent from my iPhone 5s 64Gb using TractorByNet

 

[Gator6x4]

Some time when you have an hour or so, review this NHTSA article on braking. The article covers dry and wet pavement stops. No snow or ice stops. Conventional drive and four wheel drive were used. The stopping distance was greater on wet pavement than dry so I am sure if snow and ice had been included, the stopping distances for them would have been greater.

http://www.nhtsa.gov/cars/testing/brakes/

 

[k0ua]

4wd is such a misnomer.
Normal: one wheel drive
4wd: two wheel drive
4wd with locking/limited slip rear: 3 wheel drive
AWD: true four wheel drive

do I have that correct?

Been driving my Kubota in the snow a lot this winter (no surprise!) and despite 4wd, have had to step on the diff lock numerous times to get myself though heavy snow with a load on. Need that 3 wheel drive...
Wonder if any tractor is true awd? probably too expensive..

Drew that is an oversimplification. IF traction is equal for each rear tire a 2wd vehicle drives with both rear tires and a 4wd vehicle drives with all 4. If traction is unequal then the sypder gears start to rotate on their jackshafts (1/2 shafts) then the side bevel gear on the axle with the best traction does not receive any power. Some larger tractors do have front locking diff's but I don't know of any CUT size tractors that do. If you have a spinning rear tire, you can also gently step on the spinning wheels brake and cause the other wheel with the good traction to start to pull.

 

[Egon]

Come on folks, we all know the best four on the road system is calked Perchion drive system.

 

[k0ua]

Come on folks, we all know the best four on the road system is calked Perchion drive system.

"true" 4 hoof drive

 

[daugen]

IF traction is equal for each rear tire a 2wd vehicle drives with both rear tires and a 4wd vehicle drives with all 4.

Jim, I agree on rwd with limited slip and respectfully disagree with standard 4wd. Of course, what is standard anymore.
I think I need more education...
I thought a "normal" 4wd, like I have on my Suburban is three wheel drive in 4wd High. When I have been in deep snow with the Burb,
in 4wd, not locked up in Low, only one of the front tires spun. If go down into 4wd Low, you bet, they are all pulling.

Couldn't you get a Jeep with three or four different 4wd systems? I always found that remarkably confusing from a marketing standpoint, and
then with a used car, hard to know what is really in it without finding the build info.

Driver skill and decent tires should make a lot more difference in black ice or any ice than sophisticated awd systems. Though the safety braking that is computer controlled in a modern car should help in a skid. At least it's supposed to.

 

[k0ua]

IF traction is equal for each rear tire a 2wd vehicle drives with both rear tires and a 4wd vehicle drives with all 4.

Jim, I agree on rwd with limited slip and respectfully disagree with standard 4wd. Of course, what is standard anymore.
I think I need more education...
I thought a "normal" 4wd, like I have on my Suburban is three wheel drive in 4wd High. When I have been in deep snow with the Burb,
in 4wd, not locked up in Low, only one of the front tires spun. If go down into 4wd Low, you bet, they are all pulling.

Couldn't you get a Jeep with three or four different 4wd systems? I always found that remarkably confusing from a marketing standpoint, and
then with a used car, hard to know what is really in it without finding the build info.

Driver skill and decent tires should make a lot more difference in black ice or any ice than sophisticated awd systems. Though the safety braking that is computer controlled in a modern car should help in a skid. At least it's supposed to.

Drew, I am refering to "standard" 2wd and 4wd in other words, open differentials, on both front and rear, and NO center differential. As for 4hi and 4low. the only thing going on there in a standard system is just a 2 to 1 gear reduction in the transfer case in 4low. There is no lockup or anything else going on. Now that said, there must be dozens of other systems out there with center differentials, fluid couplings, locking front and rear differentials, computer controlled traction control. and on and on. All I am saying is on an "old timey" 4wd system with an "old timey" transfer case when you are in 4wd, both driveshafts are powered from the transfer case, and both front and rear differentials are driven, then you have true 4wd right up to the point that one tire on either the front or rear starts to slip due to uneven traction with the ground. Then you could be down to just 2 tires spinning depending on the ground conditions. Of course in your tractor when you find yourself in this condition, and you press your differential lock, and lock the 2 rear axles together, they will have at least 3 wheels turning, and maybe 4 depending on traction on the front tires. Unfortunately the is not much you can do about the front tires, other than maybe turning the steering wheel to try to find a spot on the ground with more traction.

 

[Egon]

Don't forget the different length drive shafts on the front when figuring things out!

 

[xring100]

4wd is such a misnomer.
Normal: one wheel drive
4wd: two wheel drive
4wd with locking/limited slip rear: 3 wheel drive
AWD: true four wheel drive

do I have that correct?

Been driving my Kubota in the snow a lot this winter (no surprise!) and despite 4wd, have had to step on the diff lock numerous times to get myself though heavy snow with a load on. Need that 3 wheel drive...
Wonder if any tractor is true awd? probably too expensive..

M7040/60 And larger have limited slip front diff and with rear diff lock will spin all 4 tires

My buddies massey 5455 has electronic locking differentials. Why would you want true AWD your not trying to perform on a race track. As long as your spinning all tires that's all I need. Most new AWD have multiple clutches to allow torque transfer and allow slippage they can also perform torque vectoring for handling way more complicated than a simple locker

 

[xring100]

Ill wager you wont find a Subaru driver in any of those "displays".
larry

No you find them needing assistance from a jeep and a tow strap pretty typical. Driving 12 tenths of their own ability at about 3 tenths of what the car is acctually capable of

 

[daugen]

No you find them needing assistance from a jeep and a tow strap pretty typical. Driving 12 tenths of their own ability at about 3 tenths of what the car is acctually capable of

too funny, a WRX STI, yeah, he wasn't pussyfooting around. I sure hope he had winter tires on at least; that thing comes with pure summer tires.

 

[xring100]

No you find them needing assistance from a jeep and a tow strap pretty typical. Driving 12 tenths of their own ability at about 3 tenths of what the car is acctually capable of

too funny, a WRX STI, yeah, he wasn't pussyfooting around. I sure hope he had winter tires on at least; that thing comes with pure summer tires.

I'm sure he thought he was ken block right up until the point i watched him stuff it. He had a snow shoes on i did get a look at the tread blocks as i drove by him

 

[daugen]

well you really have to be hotfooting it to stuff an awd car with snow tires on a somewhat plowed road like that.
At least snow drifts don't sue...and often only hurt one's pride.
I bet he just stuffed too much snow underneath and high centered.

 

[daugen]

M7040/60 And larger have limited slip front diff and with rear diff lock will spin all 4 tires

good to know, thanks. I wonder why if we can engage the front diffs with a push of a button, why are we still all
hunting around for a little lever bar on the floor to step on? why not electronic in the rear?

 

[aczlan]

good to know, thanks. I wonder why if we can engage the front diffs with a push of a button, why are we still all
hunting around for a little lever bar on the floor to step on? why not electronic in the rear?

Mechanical lever is cheaper and more reliable.

Aaron Z