Winter handling Subaru vs dual-motor model Y

[Mvdaog]

Another question to all, do you think the off road assist function changes the torque differential to equalize it more? I notice the sensitivity to pedal changes and the traction control gets turned off but I do wonder if it also initiates power to front more than standard settings...

 

[masotime]

I found this video pretty enlightening about how the Model Y handles when it loses traction - and about the rear wheel bias.

 

[Midnightsun]

Nice video, pretty impressive. Once again any issue or tweak is easily addressed with a software upgrade. The way I see it a "Snow Mode" should reduce regen, reduce pedal input and change the bias to FWD in order to prevent the rear from wanting to spin prior to the front. IMHO this would make the car perform to most everybody's liking except there would probably be a good hit on range if using the front motor as primary that is.

 

[Mvdaog]

Nice video, pretty impressive. Once again any issue or tweak is easily addressed with a software upgrade. The way I see it a "Snow Mode" should reduce regen, reduce pedal input and change the bias to FWD in order to prevent the rear from wanting to spin prior to the front. IMHO this would make the car perform to most everybody's liking except there would probably be a good hit on range if using the front motor as primary that is.

Boy I wish they would do this!

 

[mswlogo]

I am rather experienced in snow bound condition with better than 40 years behind the wheel. As a teenager my thrill was driving in major snowstorms, the bigger the better. RWD FWD AWD 4x4 have owned them all. The Tesla handles well in the snow however in sport mode it is obvious there is too much instant power happening causing the rear end to react slightly which gets put under control very quickly. Low regen and chill mode will definitely make a difference just like when I select snow mode on the Ridgeline or other vehicle. Basically drops the power or better put, drops the sensitivity of the gas pedal. Wait, what is the gas pedal/throttle officially called on an EV. Rheostat, Dimmer, Juice injector, power pedal?

The great news is a software update can tweak this to improve over time as more data comes in, try doing that on an ICE car.

Would be a nice feature to have a single button called snow mode that simply engages chill and low regen modes with a single touch. Or have it automatically select snow mode when a couple of wheel spins are sensed with a window saying so and the option to accept or override. Hello Elon, you listening?

I always drive in Chill and all it does is delay the front from engaging. Because the gentler you accelerate the more it stays in RWD. Also been driving since 1976. I was certainly a bit disappointed with Model 3 Performance behavior that I paid $78K for. Yes, Tesla could certainly fix it in software. Albeit at a modest cost in efficiency. Problem is folks have complained about it for 3 winters and still nothing. But that’s not unlike Tesla. It certainly could happen. Why it hasn’t is beyond me.

Chill does not fix the problem.

You want the ability to crawl or cruise with equal traction (or slight more in front). With model 3/Y you simply cannot. If you crawl or cruise you’ll have 100% power in the rear and 0% in the front.

On dry pavement it works great. On slick roads the rear often has to slip or fishtail before the front engages. This is NOT GOOD. With good snows and smart driving it WILL quickly recover. But it is totally unnecessary and is risky to let the rear wheels slip (or slide sideways) at all in the first place. Which is what it what happens in practice.

You can feel it lose grip, then grab. Lose grip then grab.

Kind of like Trump. It creates a problem then brags about how he fixed it. It shouldn’t slip in the first place.

If you crawl so slow that the RWD never slips. You basically have a good driver driving a REAR WHEEL DRIVE car.

 

[mswlogo]

I found this video pretty enlightening about how the Model Y handles when it loses traction - and about the rear wheel bias.

That Video does clearly show where Y lacks ( it behaves exactly like the 3)

As opposed to Model X (or S) in the roller test video below.

Notice how with both rollers on rear or front it engages exactly the same (very smooth and quick) And with 1 free wheel in front or rear it behaves the same (and works on either challenge). And slip mode is doing exactly what it should. Allow wheels to continue to slip.

I was actually surprised the Y did that poorly on 3 rollers and never put traction on the one front wheel spinning. I thought it would eventually engage the slipping front wheel.

One thing I wish folks testing on model 3/Y rollers is do several of the same tests back to back. Once the car recognizes its in slippery conditions it might switch modes and behave different on subsequent challenges.

 

[acarney]

These tests are a little tricky since you want to make sure the vehicle hasn’t slid to the edge of the roller and gathered traction from that... but this video shows it getting going with the single front wheel test...

 

[mswlogo]

These tests are a little tricky since you want to make sure the vehicle hasn’t slid to the edge of the roller and gathered traction from that... but this video shows it getting going with the single front wheel test...

Looked like pretty damn near exactly the same results to me. My guess is, it probably did slide sideways (eventually) and one of the other wheels started grab. Or if you try long enough and goose it enough it might figure it out eventually. Are you claiming it did slide sideways and started to grip here?

Again. It's acceptable, but not great for such and expensive vehicle with all the capability that should be there. Many AWD's will do much better. Including Model S/X.

 

[laughMan]

That Video does clearly show where Y lacks ( it behaves exactly like the 3)

I was actually surprised the Y did that poorly on 3 rollers and never put traction on the one front wheel spinning. I thought it would eventually engage the slipping front wheel.

It looks like the tesla is programmed to mimic a limited slip differential on the rear wheel, and open slip differential on the front wheel.
This setup is most common for passenger car, this setup would give best traction and drivability(turning) to regular driver.

However, since tesla has full control and all the sensors, tesla should be able to detect the 3 wheel slippage and send all the power to the front wheel with traction.

 

[acarney]

Looked like pretty damn near exactly the same results to me. My guess is, it probably did slide sideways (eventually) and one of the other wheels started grab. Or if you try long enough and goose it enough it might figure it out eventually. Are you claiming it did slide sideways and started to grip here?

Again. It's acceptable, but not great for such and expensive vehicle with all the capability that should be there. Many AWD's will do much better. Including Model S/X.

I’m claiming that it was successful with just the front wheel having traction. Admittedly not as easily as the X seems to, but still...

(This is assuming the car didn’t slide off the rollers)

 

[dsmith]

TLDR: Model Y handling in winter conditions not nearly as good as Subaru

So bit of background.. I come from driving a subaru in the canadian interior mountains for the past 10 years. Prior to that was a FWD Honda. I ski and drive over mountain passes frequently and consider myself experienced in winter driving and variable conditions, as we're frequently above and below freezing, back and forth, with lots of precipitation.

I can now say after having been in a few snow storms now with the model Y, that it's handling is no where near as good as a Subaru. I had an outback and an impreza previously. My wife still drives an outback. With the subaru, we rarely ever felt fishtailing, slipping, or loss of control, even momentarily, while cornering. With the model Y, there is fishtailing with almost every cornering attempt if there's snow, packed snow, slush or ice. Going up hill, the subaru would charge up snowy and slippery conditions with confidence and mostly a straight path. With the model Y, there is quite a bit of deviation to straight, and there is some struggling in regards to keeping speed etc.

I do notice that with the off-road assist, it does help getting up our steep and windy driveway. In normal driving mode, there may have been some days I couldn't get up to my house very confidently. There are frequently FWD cars that can't make it to our house in the winter.

I should note on both cars I use studded nokian hakkapelitas. So tires are not the difference.

I did a lot of research on subarus AWD in the past, and tried to review the Tesla AWD experience from previous owners before purchasing, and was hoping it would be better than I have found it to be, is based on previous reviews. That being said, although the slipping and fishtailing are concerning, I do have confidence in the AWD system keeping me safe because it kicks in very quickly to get the car back on track, it's a very brief amount of time before the car is back on track.

So, there are going to be times when it is very slippery, that if I'm taking a corner, I will have to slow down more and be more cautious about a loss of traction, because the slightest fish tail could send me spinning in circles. In the Subaru, I knew that as long as other cars were driving on the road, I was fine no matter what the conditions. I will be more cautious and aware in the Tesla. And as my wife said, this might actually be a good thing, as in the Subaru we never truly knew the road conditions as we never felt the loss of traction. Literally, we would sometimes step out of the car and fall down as our feet couldn't get traction on the ice we were just driving on, but never felt the ice in the car. Now I know when it's slippery and when to drive more cautious.

Love the car, and I sorta expected going in it wasn't going to match the Subaru in this regard. Why would it, it's not their focus. It doesn't change my love for the car, and I still feel much more safe than most cars on the road, and certainly much better than a FWD car or a truck without any weight in the back. But for anyone wondering, I can confidently say, it doesn't match a Subaru for winter driving. I'm only writing this because I would have liked to see a review like this before purchasing, even though I would have still bought it.

I have exactly the same issue with my Y AWD with R3 winters and Chill mode and regen low enabled. Thought it was a problem with my specific car. The sliding is really unsettling.

 

[Snow Drift]

Boy I wish they would do this!

Again, there is nothing wrong with the Tesla system and it works just as well as manual Subarus (which are better systems than automatic Subarus). If you want to compare roller tests, even automatic Subarus, they are rather similar to the Tesla. Both being way better than just about any other manufacturer.

There are a few differences between your Tesla and Subaru.

1) Instant Torque - You need to adjust your right foot input in slippery conditions
2) Rear Torque at 50%+ - Your car doesn't have that, and you just aren't used to how it acts...go get a manual Subaru and it's the same
3) Wider tires - Subarus have much narrower tires stock, or available aftermarket, which are better in the snow bc they carve through snow vs plowing a wide path/floating above it. That is just a downside for all sporty cars with large performance brake calipers requiring wider rims.

My main question would be, how much are you really "fishtailing?" Is it a wide arc like a RWD car who is struggling in the snow? Or, is it really a few mm or inch and your butt is just getting nervous? If it's an inch or two and then it corrects immediately, that is the same reaction of manual Subarus (which you saw I've owned many for 15 years, plus 2 automatics).

 

[Mvdaog]

Again, there is nothing wrong with the Tesla system and it works just as well as manual Subarus (which are better systems than automatic Subarus). If you want to compare roller tests, even automatic Subarus, they are rather similar to the Tesla. Both being way better than just about any other manufacturer.

There are a few differences between your Tesla and Subaru.

1) Instant Torque - You need to adjust your right foot input in slippery conditions
2) Rear Torque at 50%+ - Your car doesn't have that, and you just aren't used to how it acts...go get a manual Subaru and it's the same
3) Wider tires - Subarus have much narrower tires stock, or available aftermarket, which are better in the snow bc they carve through snow vs plowing a wide path/floating above it. That is just a downside for all sporty cars with large performance brake calipers requiring wider rims.

My main question would be, how much are you really "fishtailing?" Is it a wide arc like a RWD car who is struggling in the snow? Or, is it really a few mm or inch and your butt is just getting nervous? If it's an inch or two and then it corrects immediately, that is the same reaction of manual Subarus (which you saw I've owned many for 15 years, plus 2 automatics).

It doesn’t work as well as manual Subaru, cmon. The Subaru is not a rwd vehicle. The Tesla is rwd until throttle applied or slipping already. The Subaru as you pointed out especially manual is basically 50/50 at all times. As others have pointed out, for everyday driving in snow on busy roadways, you don’t want to slip you want 50/50 AWD or if not possible, a slight FWD bias.

 

[rypalmer]

Bjorn rightly points out the RWD bias in the Model 3 and presumably Model Y.

I really hope they fix this soon.

 

[Snow Drift]

It doesn’t work as well as manual Subaru, cmon. The Subaru is not a rwd vehicle. The Tesla is rwd until throttle applied or slipping already. The Subaru as you pointed out especially manual is basically 50/50 at all times. As others have pointed out, for everyday driving in snow on busy roadways, you don’t want to slip you want 50/50 AWD or if not possible, a slight FWD bias.

You are used to FWD-biased AWD. I haven’t had an issue with my Teslas after 2 years using snow tires. I’ll let you know if we get a bad storm and I feel uneasy.

 

[GaryY]

Bjorn rightly points out the RWD bias in the Model 3 and presumably Model Y.

I really hope they fix this soon.

I agree. Had my first snow drive this week and experienced what Bjorn described, both on downhill regen turns with rear regen related slippage, and fishtailing with modest acceleration. I haven't had a RWD car since the 80's, and I don't think I want to go back. My wife's Forester is very boring in the snow, but you have utter confidence that the thing won't slip. If you want Subie/Audie drivers to take up "AWD" Teslas, this is not the way to go. Looks like Elon is pretty active in Twitter still, maybe if all who are Twitter users start sending it his way they'd do something about it...

 

[jcanoe]

I agree. Had my first snow drive this week and experienced what Bjorn described, both on downhill regen turns with rear regen related slippage, and fishtailing with modest acceleration. I haven't had a RWD car since the 80's, and I don't think I want to go back. My wife's Forester is very boring in the snow, but you have utter confidence that the thing won't slip. If you want Subie/Audie drivers to take up "AWD" Teslas, this is not the way to go. Looks like Elon is pretty active in Twitter still, maybe if all who are Twitter users start sending it his way they'd do something about it...

Given the rear drive bias on the Model Y would you recommend Chill Mode and Low Regenerative Braking when driving on snow covered roads or some other Driving settings? Were your recent experience driving in snow using the OE tires? Were these the Continential or the Goodyear all season tires or did your Model Y have winter tires?

 

[GaryY]

Given the rear drive bias on the Model Y would you recommend Chill Mode and Low Regenerative Braking when driving on snow covered roads or some other Driving settings? Were your recent experience driving in snow using the OE tires? Were these the Continential or the Goodyear all season tires or did your Model Y have winter tires?

I have the Pirelli Sottozeros on. I'm by no means a winter driving expert and I need to play around a lot more, but the low regen seems like a no brainer, as per above the chill mode or feathering the throttle might delay the front wheels kicking in so not as sure about that as I thought when following this thread earlier. Definitely want to play around with "off road assist" if that puts more bias towards the front, looks like one person above found that helpful the other not clearly helpful...

 

[Midnightsun]

Off road assist and slip start are rally meant for getting out of a situation or traction while creeping in very bad conditions. Both are not a good options while driving on snow covered roads as they both disable traction control. Try selecting either and you will see the no TC icon come up.

 

[laughMan]

It doesn’t work as well as manual Subaru, cmon. The Subaru is not a rwd vehicle. The Tesla is rwd until throttle applied or slipping already. The Subaru as you pointed out especially manual is basically 50/50 at all times. As others have pointed out, for everyday driving in snow on busy roadways, you don’t want to slip you want 50/50 AWD or if not possible, a slight FWD bias.

I think we all have our own opinion of what is best here. FWD biased vs. RWD biased vs. AWD biased.
This is a century old flame war topics in Subaru, BMW and Civic type R forum. I am a big Subaru, BMW, Porsche fan, and these topic are beaten beyond death.

For old school traditional sporty feel type of driver, they will prefer RWD biased. I love the fishtail steer by throttle coming out of a corner. Trade off is that the car may be less responsive in slippery condition, i.e. snowy, wet condition

For rally diehard super grippy drivers, they will love Awd all the time, but the car will be hard to drift, hence less fun in some situation. Unless you are super skillful to perform high speed 4-wheel drift, which i don’t recommend trying on public road. Being very grippy and attracting corner at insane speed is also very fun.

For normal daily driver who just need to use the car and feel confident, FWD or AWD biased will make them feel very safe and confident.

Traditional car manufacturers tune their car one way or another due their their mechanical layout, mechanical differentials, etc. Modern cars benefit a lot will all the sensors and electronic differential, so car can have a different personality with a push of a bottom.

Tesla is basically a big playstation mount in a car! Tesla should be able to program all these different mode in the car and let the driver select different settings to suit the driver.

That would be best and we don’t have to debate this topic anymore!!!