Have a 2008 Edge. The thing seems to jerk on snow covered rds. It is fine on dry rds but just jerks around when there is snow. The wrench light came on once but not all the time. Any idea what it can be?

 

FWD or AWD?

 

Is it the steering that jerks?

 

hmmm. I've wondered about this with the crossovers.
Years ago I had a Toyo Land Cruiser and it was lousy on snow! Wet, slushy snow pulled the worst. Don't know if it was potential steering geometry (although I had two and both the same) or the high center of gravity that cause the squirreliness.
But then I got a 4x4 F150. Wow! On many packed snow surfaces I can go up to 55 with complete control. Most the time 45 is more than safe. But my LC would have been all over the road.
It was clear to me that the F150's long wheel base was the difference. So I've been skeptical of the new short wheel base crossovers.
Think that's what's going on with your vehicle? (Don't know about the wrench indicator.)

 

AWD. It it just like a bucking feeling. Not all the time but every so often.

 

Any time or mostly when turning?

 

Mostly when just driving straight. The roads have fresh snow on them.

 

I think it might be the traction control working. The jerking could be the brake being applied automatically to the wheel slipping so the other wheel will take over. Or the other way around. Maybe?

 

Yeah, it sounds like the AWD fighting for grip. Ironically enough, grip is harder to smooth out than slippage: if you go from only 1-2 wheels having traction, to suddenly 3-4 wheels having traction, the car's going to surge momentarily until the computer smooths it out. Tires, road conditions, temperature, etc all contribute to that.

If you get the idiot light coming on more often, though, definitely get it checked out.