Topic: 4 wheel drive: a safety feature?

[tpl]

It is easier and cheaper to integrate the traction control/ABS/Stability control together  with the Engine computer and on those very few cars with it, active steering and active suspension.

Traction control systems use the ABS and sometimes the engine computer
Stability control uses the ABS, engine computer and steering angle active steering if fitted.

The engine computer probably just sees an input saying, power down a bit.
The ABS just sees a signal  saying, apply brake to wheel x  or release brake to wheel x.

The stability control computer is seeing inputs from steering, speed, yaw sensor, brake pedal etc and deciding which signal to send.

The effect of having proper tires for the conditions will be that  there is  less chance of these systems being needed at all.  I had to act like a hooligan in my AWD BMW with snow tires to get the stability control to work on regular winter roads at sane speeds.

[initial_D]

Just for winter safety, in normal driving condition and driver behavior, with winter tires, my experience in the CX-7, with electronic aids, beats the old school E30 325ix (VC center diff, VC rear LSD, open front diff).

However, in poor traction places, like deep snow, gravel roads, muddy roads, ... the traction feeling of the old tech beats the computer.

[safristi]

..YES/OUI it eez a SAFETY FEATURE...mais NON/But NOT a FAIL SAFE FEATURE...comprendez Vous....................... "Maude wots e tawkin' bout!!!"....

[PMREdmonton]

I'm an AWD fan, as our repeated Subaru ownership will attest.  However, it's still all about tires.  When we bought our Forester, snow tires were sold out for the winter and it actually had to sit for quite some time on it's POS all-season tires, waiting for the snow to melt.  The C230, with it's RWD, no traction control and no LSD (essentially a one-wheel-drive RWD car) would literally run away from the Forester thanks to the MB's winter tires.

1. Driver's brain.  Drive defensively and pay attention to conditions.  I bet 95% of collisions are just due to stupid driving.
2. Tires.  The right tires for the conditions.
3. AWD/ASR/ESP/etc/etc/etc/

The only thing to keep in mind for #1 is that often that bad driver causes an accident involving a responsible driver who is driving appropriately and no amount of defensive driving and car safety features can prevent all accidents.

My #1 safety rule is basic following distance - 4 seconds mandatory under poor conditions.  I actually try to get 3-4 seconds under good driving conditions if traffic permits but will not go any closer than a full 2 seconds even under optimal conditions.  Giving yourself some space gives you time to think and react and not doing anything too rash also gives the guy behind you time to react as well.