RE: Opinions: To Shift into "N" on Ice w/ABS or not to in 4x4

From: knox.james@sympatico.ca
Date: Sun Nov 15 2009 - 19:21:02 EST


Matt : does your 95 4x4 have a suregrip Diff as this is a factor during snow and ice operation.

Jim, 91 Dak 4x4
 

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> To: dakota-truck-moderator@bent.twistedbits.net
> From: teseract@moparhowto.com
> Subject: DML: Opinions: To Shift into "N" on Ice w/ABS or not to in 4x4
> Date: Sun, 15 Nov 2009 23:56:01 +0000
>
>
>
> Hello Guys,
>
> This being my first winter driving a RWD/4WD vehicle (I've always driven FWD
> cars until this point), I thought I'd ask for some opinions as to braking
> technique.
>
> My '95 4x4 is an automatic and has 4 wheel ABS. My father, when driving a RWD
> automatic car, always kicked the car into neutral under braking in snow/ice
> covered conditions as it kept the rear wheels from "pushing" the car as the
> rear tires wouldn't lock up under braking when the fronts would due to the
> engine torque overwhelming the rear brakes.
>
> Now, with ABS I'm not sure if this is true, as if you lock up all 4 wheels
> while in "N" the ABS has no way to know the vehicle is still moving, right? If
> you're in drive, the rear wheels will fight the rear brakes and keep spinning
> even if the fronts lock up, enabling the ABS to know the car is still trying to
> move. But on the other side of it, my friend's 5 speed '00 Dakota with 4 wheel
> ABS doesn't have problems with ABS kicking in with the clutch in while in 4x4,
> which would be the same as an automatic in "N". Of course the difference in
> capability in my '95 era ABS vs. '00 ABS could make a huge difference.
>
> If it's slick I'll be in 4 high of course, so if the front wheels lock, the
> rears would be forced to as well due to the diff being locked, no? If so, how
> does the ABS even know to engage? All I can figure is you have to be light on
> the pedal even under emergency braking to get the full benefit of ABS?
>
> To top it off, when trying to bleed the ABS portion of the braking system on my
> friend's '00 Dakota, we put it up on jack stands, engage 4 low in 1st gear, let
> out the clutch and rode the brakes. Even though it was suspended in mid-air
> the brakes on all 4 wheels still pulsed for as long as you held the brake down.
> (Note: put a couple lug nuts on the rear wheels to hold the drums on or they'll
> come off:) How the heck did it know to keep the ABS on? Perhaps it monitors
> engine load or clutch engagement? If so I doubt my '95 will be this advanced.
>
> So I guess I'm just looking for the best way to brake with 4 wheel ABS, an auto
> trans, with 4x4 engaged, on ice/snow...
>
> Thanks!
>
> MattB
>



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