ABS in a Box

[gadget73]

4wd does not stop better than 2wd. It just goes better.

[1987cp]

What about throwing your 4x4 into Reverse and hammering the gas? Oh, wait ... unless conditions are absolutely perfect, that'd just send you into the ditch even faster ..... :3gears:

[P72Ford]

I don't know about anyone else, but I don't do much panic braking in the snow. Evasive driving in the snow is much easier with a 4WD. Cutting the wheel and giving it some gas will often pull you through rather than causing the ass end to come around, requiring you to saw on it to get it where you need to go with any sort of control.

I also don't throw my vehicles into reverse; that requires full lock up before shifting into reverse, with a manual transmission. Its also a pretty absurd idea.

[johnunit]

wouldn't 4 wheel drive and a manual give an engine braking advantage?


I think ABS is a wash in the snow. yeah it won't dig in, but you can steer. It seems like about 50/50 to me when I've needed steering or super-fast stopping more to not hit the guy. plus, ABS on ice is far superior.

[P72Ford]

I always take advantage of engine braking, with my truck. I usually rev match my down shifts, especially when it is snowy, or wet out. I despise when folks just downshift something without blipping the gas to bring the revs up a little. In the snow, that unintentional jerk could result in loss of control.

[mrltd]

sometimes you have to get places, no matter what the weather is doing. The world does not stop just because it snowed. Unless of course you live somewhere south of DC.

South of the Mason Dixon line... everything above DC in MD shuts down because of snow. It's silly. People here have no clue how to drive in the snow. I've also found that my BMW stops faster not using the ABS in the snow. The mazda is pretty much the same, in most circumstances.

[Piece-it pete]

Maybe earlier ABS systems suck, but on my 97 MGM worked just fine, with good front tires and studs on teh back. I don't take snow days, I'll drive in anything. Rather have ABS than not. Although once coming to an intersection with construction, I hit gravel, and it did send me out past the light into the other street. Not sure if it would've happened without ABS.

Even the primitive limited slip has a use. You know how, coming to a stop sign on a slight uphill grade in the snow, it can be difficult to get going? It did help.

Pete

[86VickyLX]

Not sure if it would've happened without ABS.

Even the primitive limited slip has a use. You know how, coming to a stop sign on a slight uphill grade in the snow, it can be difficult to get going? It did help.

Pete

You would've stopped instead of going through the intersection.
The traction assist is good for non limited slip rear, since it applies brakes to the free spinning wheel. Which in turn makes the opposite wheel the freer spinning wheel, so it kinda makes an open rear a limited slip.

[1987cp]

I also don't throw my vehicles into reverse; that requires full lock up before shifting into reverse, with a manual transmission. Its also a pretty absurd idea.

Logical enough. The only time I've ever done it was when I was doing a round-the-block test run in the snow and finding out the fun way that I had no rear brakes AT ALL. (funny thing, RWD + auto trans + snow + no rear brakes = never comes to a complete stop when in gear!)

[Piece-it pete]

You would've stopped instead of going through the intersection.
The traction assist is good for non limited slip rear, since it applies brakes to the free spinning wheel. Which in turn makes the opposite wheel the freer spinning wheel, so it kinda makes an open rear a limited slip.

As so, thanks for the 'traction assist' clarification. I would've liked a off switch for it because it interfered with snow donuts.

I'm not sure about the gravel stop, because it was gravel where there usually isn't, on pavement, and I wasn't prepared (shame on me). Got lucky no traffic.

Pete

[86VickyLX]

As so, thanks for the 'traction assist' clarification. I would've liked a off switch for it because it interfered with snow donuts.

I'm not sure about the gravel stop, because it was gravel where there usually isn't, on pavement, and I wasn't prepared (shame on me). Got lucky no traffic.

Pete

Well as for an off switch, that will be added when I do get the system functioning properly. There's an internal off switch that comes from brake/on/off switch, that tells the unit to turn off traction assist (when the brakes are applied). By adding a toggle switch in series to that, the traction assist will never activate, so it would be as if it was solely an ABS system.

[Mercracer]

And also, note that wheels will slip before the trak lok grabs the other wheel. That's why it's called a limited slip, not a locker...

That is not how a Ford Trac Lok works. There is no grabbing of anything. There is no magical torque transfer. All you have is a set of clutch friction discs and plates which your side gears are preloaded against with a sheetmetal spring. The 8.8 version with wear absolutely sucks compared to the 9" version. You have several coil springs in a circle preloading the clutches in a 9".
A locker physically locks the axles together. There are no clutches or cones to "slip". When you go around a corner with a Detroit Locker, the outside wheel unlocks the diff when it spins faster. They are far less forgiving on corners with low traction.

[86VickyLX]

I must've read this passage incorrectly then. Cause the way I understand it, the differential will apply torque to the wheel with most traction...

[gadget73]

open rears apply power to the one with the least traction. A clutch-based limited slip like we have applies power roughly equally under optimal conditions, but as the clutches and stuff wear out, its less and less even. I think under new carrier conditions its something like a 60/40 split, 60% going to the side with less traction. As it wears, that number gets worse and worse until its no better than an open rear. The clutches do slip in a turn, but its not a slip then grab situation under low traction. There are other types of carrier that will actually transfer the bulk of the power to the wheel with the most traction, but then you're into stuff like a TruTrac or one of the others that uses a torsion bar arrangement instead of just the friction discs.

[86VickyLX]

open rears apply power to the one with the least traction. A clutch-based limited slip like we have applies power roughly equally under optimal conditions, but as the clutches and stuff wear out, its less and less even. I think under new carrier conditions its something like a 60/40 split, 60% going to the side with less traction. As it wears, that number gets worse and worse until its no better than an open rear. The clutches do slip in a turn, but its not a slip then grab situation under low traction. There are other types of carrier that will actually transfer the bulk of the power to the wheel with the most traction, but then you're into stuff like a TruTrac or one of the others that uses a torsion bar arrangement instead of just the friction discs.

Ok. My mistake then haha.