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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