[andrew335]

Hey guys

I have been driving my 335i xDrive this winter with new Blizzak snow tires and am extremely impressed with how the car handles in snow, sleet, etc. (Much better with the snow tires than the Continental All Seasons shipped from the factory.... the car actually comes to a stop when you brake :-))

My question is more physics related. I am wondering what the best thing to do when an AWD car begins to lose control in the rear (i.e. on ice / slush) when going around bends? I am not talking about how to drive like a maniac in poor weather conditions or pretending that I know better than the factory traction / stability control by turning it off. I am talking about the best way to react when going around bends at 20-30 MPH and the rear breaks loose due to slippery surfaces. On my old RWD E34, I was always told to give the car a little bit of gas to shift the weight of the car backwards and point the car in the direction you want to go. Does this still apply to our AWD vehicles with a rear-wheel drive bias?

Once day I'll take an advanced driving course and learn all these things, but for now, I am curious what some other people's thoughts are.

Andrew

[captainaudio]

Originally Posted by andrew335

Hey guys

I have been driving my 335i xDrive this winter with new Blizzak snow tires and am extremely impressed with how the car handles in snow, sleet, etc. (Much better with the snow tires than the Continental All Seasons shipped from the factory.... the car actually comes to a stop when you brake :-))

My question is more physics related. I am wondering what the best thing to do when an AWD car begins to lose control in the rear (i.e. on ice / slush) when going around bends? I am not talking about how to drive like a maniac in poor weather conditions or pretending that I know better than the factory traction / stability control by turning it off. I am talking about the best way to react when going around bends at 20-30 MPH and the rear breaks loose due to slippery surfaces. On my old RWD E34, I was always told to give the car a little bit of gas to shift the weight of the car backwards and point the car in the direction you want to go. Does this still apply to our AWD vehicles with a rear-wheel drive bias?

Once day I'll take an advanced driving course and learn all these things, but for now, I am curious what some other people's thoughts are.

Andrew

The same prinicples apply for FWD, AWD or RWD. What you do not want to do is anything sudden such as snapping off the accerator or hitting the brakes. Continue to apply "maintenance throttle" and look where you are trying to go (as opposed to where you are going). If you are looking where you are trying to go it become almost instinctive to steer in the proper direction. Once you the car is pointing in the proper direction be sure to straigten the wheel of you will have an even worse skid in the opposite direction. You have a fraction of a second to do this so fast hands are a big help. The Skip Barber School calls this CPO (Correct, Pause, Recover)

CA

[jopa489]

Originally Posted by captainaudio

The same prinicples apply for FWD, AWD or RWD. What you do not want to do is anything sudden such as snapping off the accerator or hitting the brakes. Continue to apply "maintenance throttle" and look where you are trying to go (as opposed to where you are going). If you are looking where you are trying to go it become almost instinctive to steer in the proper direction. Once you the car is pointing in the proper direction be sure to straigten the wheel of you will have an even worse skid in the opposite direction. You have a fraction of a second to do this so fast hands are a big help. The Skip Barber School calls this CPO (Correct, Pause, Recover)

CA

Perfectly explained. The key is to not panic; don't hammer the brakes thinking you can/should stop (you probably won't) and don't get on the throttle thinking you can swing back the other way (you will probably be worse off).

[captainaudio]

Originally Posted by jopa489

Perfectly explained. The key is to not panic; don't hammer the brakes thinking you can/should stop (you probably won't) and don't get on the throttle thinking you can swing back the other way (you will probably be worse off).

I will add one more thing, If the rear end comes around more than 90 degrees you will not be able to recover. In that case hit the brakes and push in the clutch (on an MT).

"In a spin both feet in"

CA

[andrew335]

Thanks! I was too afraid to drive the car much in the snow last year, but now that I am a year into the lease, I've been taking it through every storm and having a lot fun. Hopefully I won't experience these problems very often.

[anerbe]

I would highly recommended an unplowed parking lot free of obstacles. Best way to get this down is with experience.

[David1]

With the stability on you will not be able to anything but steer and pray. If you have the stability on DSC then you will be able to give it some gas to transfer weight and counter rotation and not fight the car.