"Full-Time" AWD Winter Mode

[diamond.g]

I wonder how much torque the front motor can put out. Maybe in a snow mode they can limit the rear to match the front.

Is the problem that people are seeing from a standstill, or is it also an issue at speed? I know MB's snow mode starts from standstill in 2nd gear instead of first. Subaru's "lock" the diff to send equal torque to all 4 wheels in first and second gear (or at least my Forester does).

 

[MoreAgain]

Breaking loose the rear end is never good even in motor sport racing.

That depends on your definition of "breaking loose." Power drifting, as fun as it can be, is not fast. But getting just past the limit of grip allows the car to rotate through the corner, improves the ability to put power down earlier out of the corner and is faster than staying under the limit of grip.

 

[ba2002]

+1 for a snow mode with fwd bias to get rid of this 30mph straight line wiggle in heavy traffic. I'm not rally racing I'm commuting.

And no it's not the torque of an EV I'm not use to, the behavior is night and day more annoying than my p90dl was.

 

[StealthP3D]

I'm not rally racing I'm commuting.

Exactly!

The rear end wiggle is easily avoided by not applying so much throttle on slippery surfaces. I'm not seeing the problem here and I've been driving on a lot of very slippery roads. I have to push the throttle well past what the surface can handle to break the rear end free. And that's with Performance winter tires (Pirelli Sottozero 2's) which have a reputation of not offering superior grip on snow and ice.

This is so much better than my previous Subaru, Mazda and Volvo's which would go into "limp" mode, even if you buried the throttle on a slippery surface.

 

[StealthP3D]

Is the problem that people are seeing from a standstill, or is it also an issue at speed?

I've been driving my P3D on slick roads all winter and I think the problem is the nut in the driver's seat. Because I haven't noticed what a few people are talking about (unless I put the car in "play mode" by purposefully giving too much throttle for conditions). In my opinion, this is the best stability and traction control I've ever driven.

If I floor it from a standstill on a sheet of ice I get the tail wiggle but it still gets up and goes! I can accelerate just as fast without the tail wiggle by only pressing the throttle down 1/8 of the way. It's the best of both worlds.

 

[Castlerock]

Stealth, we get it that you see the current condition of the control system for the car as the pinnacle of performance, and it is "Easy" to avoid the wiggle. It isn't so easy for the rest of us.

 

[diamond.g]

Stealth, we get it that you see the current condition of the control system for the car as the pinnacle of performance, and it is "Easy" to avoid the wiggle. It isn't so easy for the rest of us.

So this 5% increase in power we are supposed to be getting is a bad thing during the winter then?

Seems like more folks would rather the car severely limit torque in a winter/snow mode than deal with doing it themselves. Maybe we could get Fred Lambert or Ryan McCaffrey (sure I butchered that) to tweet Elon such a feature request.

 

[ba2002]

I've been driving my P3D on slick roads all winter and I think the problem is the nut in the driver's seat. Because I haven't noticed what a few people are talking about (unless I put the car in "play mode" by purposefully giving too much throttle for conditions). In my opinion, this is the best stability and traction control I've ever driven.

If I floor it from a standstill on a sheet of ice I get the tail wiggle but it still gets up and goes! I can accelerate just as fast without the tail wiggle by only pressing the throttle down 1/8 of the way. It's the best of both worlds.

I can easily get the wiggle with gentle acceleration. Our roads and plowing are crap in Minnesota. I get that the car will correct via traction control but it is different and imo annoying versus other AWD cars I have driven. It would be great if Tesla could fix, otherwise I will just change cars.

 

[Snow Drift]

Our winter has been horribly dry and so I've only driven one time in slush, so can I get more details on this "wiggle?"

I have spent 14 years driving AWD Subarus. I can get a "wiggle" in deep-ish snow (few inches) from a stop. The back end can slip slightly left/right as it hunkers down, then the TCS kicks on, and the car drives straight. This is with 50/50 or 41/59 full-time AWD systems with mechanical center differentials, and rear differentials; Open (08/11 WRX), Viscous (05 WRX) and TorSen (18 STI).

If the "wiggle" is as I described, it may seem abnormal to some people bc you are used to FWD-biased AWD systems. Subaru and Audi (not all Audis) actually drive all 4 tires (50/50 or ~40/60), so the powered rear tires can lose some traction and slightly slip-slide, since there rear is lighter.

Most other companies are really FWD and then at the last second try to send a little bit of torque to the rear, so the rears almost never drive the car forward. Less capable systems.

 

[ba2002]

Our winter has been horribly dry and so I've only driven one time in slush, so can I get more details on this "wiggle?"

I have spent 14 years driving AWD Subarus. I can get a "wiggle" in deep-ish snow (few inches) from a stop; if you get into a little rut. The back end can slip slightly left/right as it hunkers down, then the TCS kicks on, and the car drives straight. This is with 50/50 or 41/59 full-time AWD systems with mechanical center differentials, and rear differentials; Open (08/11 WRX), Viscous (05 WRX) and TorSen (18 STI).

Drove an outback for 6 years in New Hampshire/Vermont. Never experienced this degree of wiggle in that car.

I almost fishtailed off an off ramp 10 minutes ago. Was with traffic, partial snow and ice cover with tracks visible to pavement. Going 30 mph with traffic, out of nowhere back end slides out to 45 degrees or so. Wasn't braking or accelerating, there was a gentle curve. I assume I hit ice or lost traction from snow.

When I ordered the model 3 I made an assumption it would be similar to the model S in the snow. Obviously I was not correct. I understand how the traction control will correct it, bit it's my opinion that a system that prevents such behavior from occurring in the first place is superior. I'm not looking to have fun in the snow in bumper to bumper traffic on the interstate.

I've spent 20+ years commuting in snow. I'm not looking to drift on my commute. I just want to drive in a straight line. If Tesla doesn't do something to improve it before next season I will unfortunately have to move on.

 

[Daniel in SD]

If they ever do fix this problem they should also have a legacy "@StealthP3D" mode in honor of his relentless advocacy in the face of near universal disagreement.

 

[ba2002]

So this 5% increase in power we are supposed to be getting is a bad thing during the winter then?

Seems like more folks would rather the car severely limit torque in a winter/snow mode than deal with doing it themselves. Maybe we could get Fred Lambert or Ryan McCaffrey (sure I butchered that) to tweet Elon such a feature request.

If I limit torque application anymore I will have no forward propulsion. My p90dl had much more power from a standstill and was infinitely easier to drive in the snow.

I don't want less torque, I want more torque from the front.

 

[diamond.g]

If I limit torque application anymore I will have no forward propulsion. My p90dl had much more power from a standstill and was infinitely easier to drive in the snow.

I don't want less torque, I want more torque from the front.

Can you replicate and capture via GoPro and send to electrek or consumer reports? Seems like a quick and easy way to het them to change it. Especially if consumer reports talks about it.

 

[svp6]

After driving a week on the worst roads I've seen in Minnesota in 20 years, I am convinced that P3D software should be tweaked to allow for a snow mode. I deliberately put the Mercedes E Coupe in Sport II mode vs P3D in chill mode - and drove same roads back to back - at 20-30 mph on regular city streets. The Merc wiggles much less (almost not at all), even with the aggressive driving setting. It may be that the Michelin Pilot Alpin (Merc) are better than the Pirrelli Sottozero (Tesla), but I think the propensity to fishtail could be corrected. Again, my previous P85D did not exhibit this behavior. I would rate P3D as OK in snow, but definitely not top notch. Sure hope there is a refinement in the future. Still love the car though - the awesome Tesla preheating (vs the lame Merc pre-heat) is to me the best feature of the car in winter time.

 

[StealthP3D]

I almost fishtailed off an off ramp 10 minutes ago. Was with traffic, partial snow and ice cover with tracks visible to pavement. Going 30 mph with traffic, out of nowhere back end slides out to 45 degrees or so. Wasn't braking or accelerating, there was a gentle curve. I assume I hit ice or lost traction from snow.

Let me guess. You are one of those people who think that because you have AWD all you need are all-season radials?

I mean, it says "ALL" season right?

 

[StealthP3D]

I deliberately put the Mercedes E Coupe in Sport II mode vs P3D in chill mode - and drove same roads back to back - at 20-30 mph on regular city streets.

I don't think "Chill Mode" is designed for snow/ice - it's designed to mimic the throttle response of an ICE car to make for a more familiar experience for new EV drivers (IMO). It appears to add a delay into the driver's throttle inputs and that's the last thing you want on snow/ice. You want the torque to follow your command inputs precisely. Whether you use "Low Regen" on snow/ice is certainly a matter of personal preference (the Owner's Manual recommends it) but I have found Chill Mode to be counter-productive, especially if it's really slick.

 

[StealthP3D]

If they ever do fix this problem they should also have a legacy "@StealthP3D" mode in honor of his relentless advocacy in the face of near universal disagreement.

It's only "universal disagreement" in your mind. Most people are having no issues.

I've been driving on snow and ice almost every day this winter and it's pretty obvious to me that my car is sticking to the road better than most other cars out there with winter tires. Maybe the Pirelli Sottozero's are just that good but experience with other tires tells me that's not the case - the Model 3 is just naturally a pleasure to drive in the slippery stuff.

 

[Daniel in SD]

It's only "universal disagreement" in your mind. Most people are having no issues.

I've been driving on snow and ice almost every day this winter and it's pretty obvious to me that my car is sticking to the road better than most other cars out there with winter tires. Maybe the Pirelli Sottozero's are just that good but experience with other tires tells me that's not the case - the Model 3 is just naturally a pleasure to drive in the slippery stuff.

Haha. This thread is now 9 pages long and I'm not sure anyone has agreed with you. The Model 3 sticks to the road just about exactly as well as any other car when equipped with the same tires. The problem is the AWD system doesn't apply any torque to the front wheels until the rear wheels slip. This is likely to improve efficiency and handling in dry conditions which is great but unless they can more seamlessly detect rear wheel slippage a mode is needed for snow and ice. It sounds like you may be the only one with a software build that does that

 

[StealthP3D]

The problem is the AWD system doesn't apply any torque to the front wheels until the rear wheels slip. This is likely to improve efficiency and handling in dry conditions which is great but unless they can more seamlessly detect rear wheel slippage a mode is needed for snow and ice.

It's actually false that no torque is applied to the front wheels until the rear slip. Yes, it does send more torque to the rear under most situations (thankfully). Any experienced driver who has driven the AWD on the snow/ice can tell this. We have a RWD and AWD to compare. This misunderstanding was furthered when the Model 3 owners working on CAN bus data erroneously mapped it. They have since admitted their earlier mapping was wrong but it's apparent it's still not correct. Because the kW draw attributed to the two drive motors is still larger than the kW load on the battery. That's impossible.

Those guys are doing great work on hacking into the CAN bus data but they need more time before they get reliable data on the torque splits. In the meantime, it would be helpful if you would refrain from spreading misinformation about how the torque is distributed on snow/ice when any experienced snow/ice driver who drives on the stuff almost every day can tell that what you are saying is simply false.

 

[Daniel in SD]

It's actually false that no torque is applied to the front wheels until the rear slip. Yes, it does send more torque to the rear under most situations (thankfully). Any experienced driver who has driven the AWD on the snow/ice can tell this. We have a RWD and AWD to compare. This misunderstanding was furthered when the Model 3 owners working on CAN bus data erroneously mapped it. They have since admitted their earlier mapping was wrong but it's apparent it's still not correct. Because the kW draw attributed to the two drive motors is still larger than the kW load on the battery. That's impossible.

Those guys are doing great work on hacking into the CAN bus data but they need more time before they get reliable data on the torque splits. In the meantime, it would be helpful if you would refrain from spreading misinformation about how the torque is distributed on snow/ice when any experienced snow/ice driver who drives on the stuff almost every day can tell that what you are saying is simply false.

I'm tempted to put it on my lift to find out... It sure feels like it.
From an efficiency standpoint it would make sense to send all torque to the rear wheels at low loads.