How is Model 3 RWD in the snow?

[SageBrush]

Physics says otherwise

Show the physics then.
Show how 4 tyres with inferior grip stop a car in less distance than 4 tyres with superior grip.

And before you start babbling about weight distribution, ask yourself how much weight redistribution happens in a car with no or minimal traction.

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General reading on the topic for those more interested in results than physics:
NerdWallet
No Name Blog
Bridgestone
Tire Rack
Consumer Reports

A snippet from CR:

All-wheel drive is about getting your car moving from a dead stop—not about braking or steering—and you should be aware of its limitations.

 

[SageBrush]

The difference of the drivetrain does little to aid braking on snow and ice.

Correct

A good set of winter tires can be a tremendous help in giving RWD vehicles secure traction and handling in snowy and icy conditions. But it doesn’t overcome the benefit of AWD in the majority of variation in true winter driving. Heavy snow, deep snow, ice, un-plowed & driven roads, and even uphill.

It will always be true that the same car with the same tires will benefit in certain ways from AWD in winter conditions. What is categorically NOT correct is saying that AWD+4-seasons is safer than RWD+winter tires in winter conditions.

 

[pnwadventures]

This discussion became a little hard to parse because two complementary yet distinct points have been conflated: stopping/braking and accelerating/handling.

The former is 100% tires, the latter is a mix of drivetrain & tires. In a normal driving situation, it’s impossible to tease these apart as both are involved.

Rather than split hairs, the simple truth is that nothing beats AWD on snow tires. Once you detract from that - either 2WD or non-snow tires - then some (potentially critical) element of winter driving is going to suffer, such as stopping distance, not getting stuck, cornering, hill ascension, or even finding your car in the exact same spot after leaving it parked on an icy incline.

 

[valaeyron]

This discussion became a little hard to parse because two complementary yet distinct points have been conflated: stopping/braking and accelerating/handling.

The former is 100% tires, the latter is a mix of drivetrain & tires. In a normal driving situation, it’s impossible to tease these apart as both are involved.

Rather than split hairs, the simple truth is that nothing beats AWD on snow tires. Once you detract from that - either 2WD or non-snow tires - then some (potentially critical) element of winter driving is going to suffer, such as stopping distance, not getting stuck, cornering, hill ascension, or even finding your car in the exact same spot after leaving it parked on an icy incline.

I submit that 6 wheel drive with snow tires is better.

 

[Houshmanzilli]

AWD will generally pull from a dig easier (even with all seasons vs RWD with snows), but all cars have all-wheel brakes, so stopping should be about the same. Really RWD might be marginally better for stopping due to being lighter. Turns - from a pure steering point of view they should be similar, but for effective winter driving you need to throttle steer as well, in which case AWD will have the advantage.

Nicely explained. There are lots Cade studies conducted by tire manufacturers anyone can lookup. There are also many experipments conducted on YouTube from automotive and driving based channels as well that test all this in various conditions with controlled variables.

 

[KenC]

I submit that 6 wheel drive with snow tires is better.

It worked in F1.

 

[tm1v2]

I submit that 6 wheel drive with snow tires is better.

Tracks are best, but many-wheel drive is cool too.

 

[SageBrush]

the latter [handling/acceleration] is a mix of drivetrain & tires

This is where it gets a bit tricky. First, handling and acceleration have things in common but they are not identical. So the conclusions reached for one may not apply to the other. This is all the more true in the era of EV traction control.

Second, I certainly agree with you that better tire grip and AWD are synergistic; that is, both together are better than either one alone. But what about the scenario of one or the other ? I tend to think of them as +/- similar performance, but I doubt there is an answer that fits all situations.

 

[tm1v2]

AWD so is widely available these days, if you're concerned about maximum performance in the snow I see little reason to bother with 2WD.

Snow tires vs AWD is a silly argument IMO. Buy the car you want, and then put on the tires you want.

It bears mentioning that AWD systems are not all equal, not even close. That's true between ICE AWD drivetrains and between EV ones. If you want maximum traction some are much better than others.

 

[timk225]

This winter, with my '18 RWD 3, I've been driving to an area out in the middle of nowhere for work, where the roads are not plowed first. I've been driving in Pittsburgh winters for 30+ years, but this winter has been a little more annoying. On hard packed snowy roads, the all season tires suck. I tried winter tires the first winter I had it, and it threw the regen all to hell and back, they were off the car within a week. The traction control does too good of a job at stopping wheelspin, and even when I engage slip start, it still interferes way too much. It needs to get out of the way and let me handle it.

I remember the good old days of 1997-2004 in my 1971 Plymouth Valiant. With a highly modified 225 Slant 6, wide ratio 904, rebuilt limited slip differential and a halfway decent set of winter tires, that thing would go almost anywhere. Being a completely analog car with no nanny controls, when I pressed on the gas pedal to get power, I got as much as I wanted. I could hang the rear end way out there during 90 degree intersection turns, and drive how I wanted to. It was fun. And it had a really good heater in it too for such an old car.

 

[tm1v2]

@timk225 I agree so much about how annoying undefeatable stability control and traction control are. Most of my ICE cars didn't have those nannies at all, and the one that did let me turn them off completely, so I kept them off always and never once felt any reason to want them. (That car had great AWD with amazing traction.)

For our recent Model 3 purchase I insisted on the P because of Track Mode. I've read even Track Mode's "stability assist" slider doesn't let you turn the nannies off completely, but so far it's given me plenty of leeway to have proper control and fun, though I haven't driven the car in the snow yet.

If I had a non-P Model 3 the MPP Party Box would be an essential mod to me.

 

[Park2670]

I am glad so many people commented on that post saying RWD is dangerous when it snows. Yes, on summer tires ANY car is dangerous in the snow.

A RWD car, in the snow, with snow tires, is completely capable in most situations. Of course, an AWD car with snow tires will be better. But an AWD on all seasons won't be able to stop nearly as good as any other car with snow tires on it.

 

[SageBrush]

AWD will generally pull from a dig easier (even with all seasons vs RWD with snows), but all cars have all-wheel brakes, so stopping should be about the same.

Stopping with winter tires will be *much* better compared to AWD with all seasons

 

[terranx]

Stopping with winter tires will be *much* better compared to AWD with all seasons

Implication being stopping with the same tires.

 

[SageBrush]

Implication being stopping with the same tires.

If you were trying to say that in and of itself AWD does not improve braking compared to 2WD, I agree.

 

[terranx]

If you were trying to say that in and of itself AWD does not improve braking compared to 2WD, I agree.

Yes, that is the point.

Acceleration: AWD >> RWD to the point where the tires don't matter anymore. Especially in cars with open differentials (like Teslas)
Braking: AWD ~= RWD with same tires
Turning: AWD > RWD with same tires

 

[SageBrush]

I watched a youTube video on this question today (of AWD+AS Vs 2WD+Winters) and as expected, the AWD was very impressive launching in snow and slick conditions, but pretty darn poor in stopping. As others have commented often, it is a dangerous combination because it gives unwary drivers a felling of confidence that they have superior traction and an ability to safely drive faster than without AWD.

 

[tm1v2]

I watched a youTube video on this question today (of AWD+AS Vs 2WD+Winters) and as expected, the AWD was very impressive launching in snow and slick conditions, but pretty darn poor in stopping. As others have commented often, it is a dangerous combination because it gives unwary drivers a felling of confidence that they have superior traction and an ability to safely drive faster than without AWD.

I can safely drive faster on snow and ice in many situations and conditions with a good AWD system than with 2WD, assuming the same winter tires on both. That is confidence from experience.

An AWD badge gives a false sense of confidence to people who think it lets them drive on snow and ice with their worn down all-seasons like it's pavement. In other words, people who don't really know how to drive, and don't even realize they don't know.

If you can't control your car in a slide, slow the f*** down and find someplace safe to learn and practice, no matter if you have RWD or FWD or AWD.

 

[SageBrush]

If you can't control your car in a slide, slow the f*** down

If you are sliding with traffic around you, slow the f*** down.

 

[tm1v2]

If you are sliding with traffic around you, slow the f*** down.

Safe to learn and practice means room to make big mistakes. Not just no traffic around, but no ditches or cliff edges or snow covered curbs or narrow roads or lamp posts or such...just wide empty road or big open lot with room to practice and play.

Once you have a handle on what you're doing, then safe to take turns fast with all 4 wheels spinning means nobody right near you, but you can do it with less (not zero!) margin for error in terms of road edges and hazards, if you're confident in your control and judgement.

Be very aware of how much your traction can vary between snow and ice, and even between different textures of snow. If you can't tell exactly what surface the car's weight will be on, be ready for the worst. Don't be that person making emergency crews rescue you from sliding off the road for no good reason. (And especially don't be that person sliding into other people!)