My impreza felt like a RWD!

[grape]

It was a heavy snow in Toronto, a couple of hours ago, I drove my impreza
2.5i heading home. When almost finished a 90 degree turn, I give a bit
throttle, then, it suddenly produce an over steering! almost hit the curb,
like those RWD.... and then it immediately produced some kinda of noise of
"clank", and the car felt like the front and rear got locked up or soo....


ain't AWD supposed to be safer on snow?! how come I got this oversteering?
it happend when almost finished the turn and applying a bit throttle.

5speed manual.

 

[nothermark]

It was a heavy snow in Toronto, a couple of hours ago, I drove my impreza
2.5i heading home. When almost finished a 90 degree turn, I give a bit
throttle, then, it suddenly produce an over steering! almost hit the curb,
like those RWD.... and then it immediately produced some kinda of noise of
"clank", and the car felt like the front and rear got locked up or soo....


ain't AWD supposed to be safer on snow?! how come I got this oversteering?
it happend when almost finished the turn and applying a bit throttle.

5speed manual.

safer - yes, better traction - yes, bombproof traction- no. From the
sound of things one end lost traction but the other didn't, or you
were not aware it did. AWD or 4WD let one get through a lot of
conditions a 2WD will have a problem with but one can still exceed the
traction limits. Those limits drop pretty low on snow and very low on
ice. On the downside can just get going faster so the accident can be
more spectacular if you lose control. On the upside you are less
likely to lose control if you are prudent about driving conditions.

 

[Mike]

I did this on dry pavment in my WRX. Takeing a sharp left, hit the gas
coming out of the turn and i guess since most of the weight was shifted to
the right the left rear tire lit up, rear end kicked out, started going
sideways, front end was heading into the on coming lane. I was turning into
the slide , but still couldnt get it stright without letting off the gas..
Didnt think this could happen with AWD. How does the sub AWD work ? Do both
sides get equel power or does power get diverted to the side getting
traction when the other is loseing traction ?

 

[DG]

Isn't this called drifting? a racing skill actually...

 

[CompUser]

Isn't this called drifting? a racing skill actually...

No, he described wheel-lift snap oversteer.
Drifting is quite different.

 

[DG]

Thanks for the correction. I clearly haven't mastered either manuver in my
WRX....yet

 

[John]

It was a heavy snow in Toronto, a couple of hours ago, I drove my impreza
2.5i heading home. When almost finished a 90 degree turn, I give a bit
throttle, then, it suddenly produce an over steering! almost hit the curb,
like those RWD.... and then it immediately produced some kinda of noise of
"clank", and the car felt like the front and rear got locked up or soo....


ain't AWD supposed to be safer on snow?! how come I got this oversteering?
it happend when almost finished the turn and applying a bit throttle.

5speed manual.

All AWD and 4WD vehicles will do this if the rear end loses traction. It
happens in my 95 Legacy and it occurred in both my 83 and 86 Toyota 4WD
wagons. Also happens in my 91 XR7 : )
Giving too much throttle even in a straight line will get the RWs to lose
traction. If in a corner the momentum is going to carry you through. You
*could* try to add more weight to the rear but once the throttle gets the
wheels lose, it only adds as more momentum. My suggestion is less throttle
or downshift prior to the turn, not in it.

 

[jcz]

Dedicated snow tires make a huge difference. AWD is not invincible on
snow or ice.

 

[jcz]

I don't believe giving any throttle in a turn in the snow is a good
idea.

 

[Michael Pardee]

I don't believe giving any throttle in a turn in the snow is a good idea.

I think that about covers it. AWD is better than 2WD, and (in my experience)
better on paved roads than 4WD. Disclaimer: I have limited experience with
AWD, and none with the Subaru variety. 4WD forces at least one wheel to slip
in turns, while AWD allows some slippage... and that means a certain amount
of unpredictability if the throttle or surface changes suddenly. On broken
surfaces, 4WD is the way to go, but on slippery pavement I prefer 2WD to
4WD. AWD and careful driving is the choice to make there.

Mike

 

[nothermark]

If you want to know the physics based reasons go find a book on racing
cars but the bottom line is that once the wheels start to spin you
must let off on the gas to let them get traction again. About the
only time this is not true is when the surface changes. Examples
would be an ice patch or pile of wet leaves. There you lose it on the
patch then get it back on clear pavement.

 

[Jim Stewart]

safer - yes, better traction - yes, bombproof traction- no. From the
sound of things one end lost traction but the other didn't, or you
were not aware it did. AWD or 4WD let one get through a lot of
conditions a 2WD will have a problem with but one can still exceed the
traction limits. Those limits drop pretty low on snow and very low on
ice. On the downside can just get going faster so the accident can be
more spectacular if you lose control. On the upside you are less
likely to lose control if you are prudent about driving conditions.

No manner of traction control can overcome
the laws of physics.

 

[oldslowbenter]

No manner of traction control can overcome
the laws of physics.

I have experienced the oversteer affect, but I think that it's the front end
steering in, rather than the back swinging out, and I think the 'thunk' is
the traction wheel getting power from the transfer case. Maybe I held the
turn a few microseconds too long before steeringout of the turn. Quite
startling when it happens and it caught me off-guard. I think the best way
to handle this is to use the brakes and trust the anti-lock.