Automatic snow tires throw chains at your wheels [video] | Hacker News Reader

Automatic snow tires throw chains at your wheels [video]

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Granted a passenger car is not a heavy truck or bus, but living in the upper Midwest, I've learned that snow tires make a huge difference for winter driving. I'd heard the folklore that snow tires are more important than all wheel drive for handling on both snow and ice, and having used them for a few years now, I'm a believer. So called "all season" tires are not snow tires.

You can get a complete set of snow tires, mounted and balanced on rims, delivered to your door by Tire Rack (no relationship, just a happy customer). If you don't want to change the tires yourself, there are shops that will change them out and store them for you.

Snow tires are great but they really don't help with ice. The only reliable ice traction in my experience are tire chains or studs.

They do help even on ice compared to all seasons or summer tires: https://youtu.be/GlYEMH10Z4s?t=39. Studs definitely are better on ice, but cause issues on dry pavement and may be illegal to use depending on the state and time of year.

I've used all kinds of traction tires in real world conditions over the years and say otherwise. Yes, brand new snow tires are far better than all seasons on ice. But after a few months the soft rubber on them will deteriorate and they're just the same as all season, but now with the added 'benefit' that you have no idea this has happened until you try to brake on ice and it doesnt grip as well anymore. I honestly think snow tires on ice do more harm by making people without winter driving experience overconfident in their abilities (same problem with AWD).

That said snow tires are still spectacular and necessary in snow. I buy and use snow tires every winter season. They are invaluable. I just am saying don't drive with them on ice and expect to have any better traction.

In real ice events/situations the tire chains come out or you just stay off the road, it's that simple. No amount of perceived driver skill, AWD techno buzzwords, etc. will save you on ice--you need hardened steel cutting into the ice.

I appreciate your comment. While I think my snow tires have helped on ice, I'm hesitant to make a broad claim about them without quantitative evidence to back me up. And I certainly take all precautions if there might be ice, ranging from slowing down a lot, to staying home.

Now, I love my carbide studded bicycle tires. Those definitely do work on ice. But once again, staying upright on ice involves a combination of those tires and other precautions such as slowing down.

Studded bicycle tyres work great on wet leaves too.

The size of the bicycle tires are also important, and the air pressure. I changed to a fatbike without metal studs this year and now I can bike with very low pressure. Normally around 0.5 bar when bumpy and slippery, it works like a charm as long as it's not smooth ice covered with snow. The tires shape themselves around all the cracks and bumps and gives tracktion almost everywhere. The old bike with thinner wheels didn't have as good comfort in winter even with new studded tires because I could not ride it at that low pressure without getting damages to the rubber.

I live in an area of Sweden that has ice and snow at least 4 months per year. Still thinking of buying studded tires for the fatbike but want to see how I'm doing with these, the rubber is nice and soft even at -20 degrees so I think I might be good enough with this solution.

Expanding on your excellent answer, the real difference between studded and unstudded winter tires isn't just how the perform on ice, but on ice as the temperature approaches freezing. At very cold temps, the unstudded actually have an advantage. The ice is too hard for the studs to penetrate, and the softer rubber of the studless stops a bit shorter.

But as the temperature warms to freezing and the ice gets softer, the studs really come into their own. The studded tires have an even shorter stopping distance than they did at 0F/-20C, but the unstudded start sliding and almost never stop. In the worst case, the stopping distance can be almost 3x longer than the studded!

Here's an accurate (although biased) summary of a Russian study about this: http://www.skstuds.ca/2015/10/04/the-studless-tire-deception.... Clicking through to the Google translate of the original gives even more info.

I live in Vermont, and use studless winter tires for the winter months. On snow they are great. On cold clear roads, they are much better than All Seasons. But if you hit black ice on a thawing road, you need to know that they will not stop you the way a studded tire would.

This fits my personal experience. I don’t think I have ever slipped in snow when using snow tires. In fact, I have seen big all-wheel drives slip and slide in all season tires while my small front-wheel drive maneuvered just fine in snow tires. Driving in ice, on the other hand, feels just about as slick with or without snow tires.

I wish we'd charge a tax here in WA for people using studs. They're legal for part of the year but I see taxis and other cars rocking them all winter in Seattle tearing up the road, you can hear them coming. We get maybe a week of stud worthy traffic a year. This is not folks going up the mountains to ski. But they tear up the road something fierce.

This is such a common statement from people who don't own winter tires.

I own winter tires and he’s right. They’re not a marked improvement on just ice. You’re normally not on just ice a lot though thankfully.

Real winter tires? Because quality winter tires are awesome on ice.

Yes, and no they aren’t, you’re probably just thinking of icy conditions, where there is ice, snow, salt, bare asphalt, etc. They’re great for that.

But I’ve driven across a frozen Lake Erie with no snow (we used do that sometimes to get to the islands when the ice is thick enough) and it’s just pure ice. Nothing but chains makes much difference then.

But outside of rare stuff like that you’re not often on just ice, so OPs comment, while I agree with it in fact, it’s kind of an “aaaaaactually”.

Ah, literal ice - well, certainly that is out of the normal use for the tires? Snow tires definitely help for "road ice" or "snow that has become ice" - I had to once drive up a fairly steep driveway of "snow that was now ice" (where you could not walk up it without crampons) and my snow tires did a great job with my AWD - I was extremely impressed.

Having had snow tyres on previous cars I can confirm that these tyres are no better than regular tyres if you hit a patch of black ice. There's basically no traction available. Now, if you've invested in studs for your winter tyres then it's a bit of a different story. But the parent is mostly correct.

The advantage of snow tires on ice is that they are designed to have a stiffer sidewall. Studded snows are better, yes, but even regular snows are a step up on icy road conditions.

I don't think that is backed up by data. If you switch from regular summer tyres to good winter tyres, the braking distance on ice from 40 km/h decreases from 105 metres to 52 metres (or 65 metres on shittier European winter tyres). Switching to studded tyres would then decrease it to 33 metres.

https://www.rengas24.com/images/breaking-distance/breaking-d...

Get sypes cut in them. Makes a noticeable difference on ice.

It won’t help with wet ice, but nothing really does. I’ve watched a truck in chains slide on that mess.

FYI there is a new category of tire called "all weather", which have the little mountain-snowflake symbol used for snow tires. They're basically all-seasons rated for snow. I haven't seen a comparison against pure snow tires, but they do perform much better than all-seasons in snow.

Do you mean the 3 mountain snowflake rating? I recently switched from some AT tires without it to those with it and while they definitely don't rise to the level of snow tires, the 3 mountain snowflake rating does seem to be legit. I don't do anything extreme in the snow but I don't want to turn around, either, and they go further than similar AT tires without.

Do you get both sets of tyres balanced?

Yes, mounting tires on rims (even re-mounting) always requires balancing. Since practically nobody can mount their own tires, balancing is one of those things that "just happens" behind the scenes.

Most people I know who have snow tires opt for a second set of (typically cheap) rims, and the wheel set comes mounted and balanced. In my case, I change them out when needed, otherwise if I'm scheduled for something like an oil change, I just toss them in the car and have the shop do it.

They are always marked with chalk for which one is which (i.e., right, left, front, back).

They’re pretty great. Eg the michellean crossclimate 2. Unless you live somewhere with months and months of ice, they’re probably the way to go these days. Most of the performance, much less wear/noise/warm temp problems

That sounds suspiciously like a rebranding of "M&S rated" all-seasons.

Here's one comparison:

https://toptirereview.com/michelin-x-ice-snow-vs-michelin-cr...

In this test, the CrossClimate all seasons were within 10% of the snow performance of the X-Ice snow tires.

>> They're basically all-seasons rated for snow.

Ya. They are the bare minimum to qualify for that label. They are essentially the worse snow tires that can still be called snow tires. It's all marketing hype, which becomes dangerous when stupid people rely upon it to make safety decisions.

Can confirm. I’ve owned front wheel and all wheel drive minivans, both with all season and proper snow tires.

Snow tires are much more effective than all wheel drive, but having both is (obviously) better.

Was just going to say, just have both?

In my experience, AWD with no snow tires is better than 2WD with snow tires. AWD and snow tires is tops. YMMV. Source: Montana.

> I'd heard the folklore that snow tires are more important than all wheel drive for handling on both snow and ice

All wheel drive helps zero with winter conditions, except for going uphill or some other acceleration-equivalent action. Quite the opposite really - many people have experienced how with 4x4 you don't get a warning before you just lose your grip and off the road you go. For the record I'm driving a 4x4, but using summer tires in the winter, with or without engaging 4x4, the car will simply be like Bambi on the ice. Going downhill would mean that I wouldn't stop before hitting something or ending up in the sea. 4x4 doesn't matter for that.

The first thing I do when getting a new car (I always by second hand cars - not that I buy them often, but I'm old enough to have gone through a few) is to buy the best possible summer and winter tires I can get, particularly the latter. That goes before any other investment in the car. I had enough of bad tires when I was very young and without any money.

EditAdd: Many people comment about ice and studded tires. Yes, studded tires are better, not just on ice, but on many kinds of packed snow conditions as well. For some conditions they are the only good option (interestingly enough, this does not always mean that they're better than studless tires on all kinds of ice - it depends on the ice). However, if there's a lot of bare asphalt around, as is often the case when there's a lot of traffic, then studs aren't particularly popular (road wear etc), and in some countries in Europe with lots of bare roads in the winter they're illegal (e.g. Germany IIRC).

As for winter tires without studs, on ice, be aware that there are great differences between brands and types. My father's car had stud-less winter tires while my car had studded tires, and I drove both cars on the same roads and his car behaved well, even on ice or "glassy" snow. But then the tires got old and he replaced with brand new tires, but a different type - much newer, so should be better, right? Not so. Very different to drive. Dangerous I would say, and in fact he got into an accident because of that. I checked that place with my own car afterwards, and no doubt his old tires would have held up just fine.

AWD != 4x4. AWD + traction control absolutely helps driving on snow and ice with appropriate tyres.

If you are driving with summer tyres on ice, then of course you are going to be skittering all over the place.

When going downhill on ice, again your tyres are going to make ALL the difference. You shouldnt be trying to stop going downhill on ice anyway. You should be descending at a constant and controlled speed.

I think "AWD" today is used to mean "anything that isn't 2WD". So whether it's a full time 4x4 or something that is mostly-fwd-but-rwd-when-slipping or something else isn't part of the nomenclature. It simply means "something more than 2WD at least some of the time". There has been an endless debate as to whether 4WD or AWD are the same or different, whether only "symmetric" or "full time" counts as one or the other. But these days with hybrid drives, traction control shifting drive front/back etc., it's just too complex to keep apart any more.

Not really - AWD is effectively non-braking traction control by varying the power distribution to each axle (and on some modern electric drivetrains, each wheel). 4wd provides constant power to both axles.

I think of it more as an outdated distinction. First of all with motors on each wheel and no communication between front/rear in many cases, the distinction becomes blurry.

Further many manufacturers have names like “AWD” (volvo and others) or “4matic” (MB) or “4motion” (VW) to label their take on more-than-2wd, whether or not their variant is awd or 4WD (or both) in the traditional sense. Some "AWD" models will be electric with 1 motor per axle, or 3 motors (1 front 2 rear) etc. Some others are ICE with traditional drive shaft to the rear wheel axle, which in some cases will drive 50/50 and in some cases variable. Others still are hybrids wth no prop shaft but instead a rear electric motor etc.

Its not outdated. There may be multiple variations on AWD (as i mentioned, some can vary power to individual wheels, rather than just the axles), but 4WD (or 4x4) is categorically not AWD.

Doesn't traction control further blur that? Given that traction control is now required almost everywhere, and involves cutting power to individual wheels (Not like ESP using brakes), at what point does traction control cutting power to individual wheels or axles dynamically in a 4x4/4WD system make it an "AWD" instead?

Perhaps those vehicles that use 4x4 in the tradtional sense are such that you have to engage it and that effectively cuts also any traction control - and then you disengage for normal driving?

Traction control on an AWD system can be composed of power management (overall torque output), power distribution (how much power goes to each axle/wheel) and braking (slowing down individual wheels).

Traction control on a 4WD can only consist of power management and braking, because there is no way to vary the distribution (otherwise it would be AWD, not 4WD).

There are some systems that under certain conditions will switch from 2WD to 4WD. Those systems are NOT considered AWD and dont have the benefits thereof.

FYI, ESP (Electronic Stability Program) is just a brand term for an ESC (Electronic Stability Control) which covers both TCS and ABS. When people talk about "traction control" they usually mean the entire ESC subsystem.

I think part of why I consider them to be one and the same is because in the total absence of "true" 4WD/4x4 (approximately no one drives pickup trucks in Europe, I'm guessing that's where the true 4x4 still lives in the US) so the 4WD/2WD moniker has been used for 2WD/AWD as in "Will you get the 2WD or 4WD tesla is used somewhat sloppily?". It seems car manufacturers though are still careful not to call anything 4WD or 4x4 when it's not.

Lots of "true" 4WD vehicles in europe. Also, lots of AWD vehicles with lockable centre differentials (which effectively makes them 4WD when needed).

But thats not your typical SUV, no.

I think there is more nuance here. A 4x4 with a locked center diff and open front and rear diffs acts just like many AWD implementations.

That same 4x4 with limited slip diffs on front and/or rear is just like other AWD implementations.

And that same 4x4 with locked front and/or rear diffs is just like yet other AWD implementations.

> A 4x4 with a locked center diff and open front and rear diffs acts just like many AWD implementations.

Thats simply not true. It wouldnt be AWD if it cant adjust the power supplied to each axle. Thats the primary distinction.

Not all AWD implementations can adjust power per axle. The vast majority just use a center diff that is either open or limited slip. Both of those configurations are also used in some 4WD systems.

The primary distinction is that AWD is full time, while 4WD is part time and vehicles run in 2WD until the transfer case connects the second diff/axle.

Actual torque vectoring AWD systems are fairly rare and expensive compared to the AWD that has existed for 50 years, though they are becoming more common.

Here’s a good illustration of the different AWD implementations; I think you’ll find that a simple open center diff is still considered AWD and is still pretty common: https://www.caranddriver.com/features/a15102281/best-all-whe...

To clarify, your initial statement said "a locked center diff" would be a valid form of AWD, which is what i was contesting.

All the differentials mentioned in your link allow for variable power distribution to each axle. Thats the whole purpose of a center differential.

Of course, not all AWD are created equal. Some apply equal torque to all wheels (i.e. open), some prefer a single axle (e.g. limited slip), some aren't controlled by the wheels but by the ESC (e.g. electronically actuated clutch packs). I suppose in electric cars where each axle is driven independently they dont even need a center differential (but I have no knowledge there).

But its an interesting link nonetheless - it was certainly educational - so thanks!

I do agree, however, that a full-time 4WD (which have a central diff, unlike part-time 4WD which generally do not) are effectively indistinguishable from an AWD with a simple open center diff. Of course, those are the least effective types of AWD - but the 4WD at least has the ability to lock that diff and likely has a multi-speed transfer case :)

>> First of all with motors on each wheel and no communication between front/rear in many cases, the distinction becomes blurry.

Which cars have motors on each wheel? That is maybe 0.01% of vehicles on the road. (Electric busses?) And even then, AWD/FWD distinctions can matter in how those motors interact. Electric or IC, so long as power is delivered through four wheels there will be different styles and techniques for balancing that power for whatever reasons occur at a particular time.

Nothing yet, but the next porsche electric drivetrain supposedly will:

https://newsroom.porsche.com/en/2019/technology/porsche-engi...

Agree. We have a Tacoma that has 4WD and it is the absolute dumbest implementation. Contrast that to the Subaru with AWD and it is a completely different driving experience. We go with studs on the Tacoma for that reason, and get by with regular snows on the Subie.

It doesn't mean any difference when you're trying to slow down downhill. As you're saying, "your tyres are going to make ALL the difference." Which is exactly what I said - 4x4 or AWD doesn't help anything with that.

Well actually... 4x4 is worse for going downhill on ice. If one axle loses traction (which would be much more likely on summer tyres), the other can initiate a slide.

This is the exact reason people dont like 4x4 on ice. AWD (usually) lessens the problem - which is why i said they absolutely help with the correct tyres.

And again - DONT SLOW DOWN when going down hill. Your brakes WILL lock a wheel and you WILL slide. Slow down BEFORE you go downhill. If you havent experienced this truth, then you havent driven downhill on ice (which is preferable).

Yeah 4xAWD (let’s piss everyone off) helps maintain action when you’re driving IN the snow (you have a slightly better chance of not getting stuck if you can power all your wheels and have appropriately calibrated antislip).

But losing control because of ice can happen no matter how many driven or traction control wheels you have. And all wheels are basically skis when you’re skidding at 90° to the direction of travel. In fact, in some skids front wheel drive will be the best as at least you have a chance of powersteering out.

The real trick is to not start the skid at all. Sloooooooow down before you’re driving sideways.

> In fact, in some skids front wheel drive will be the best as at least you have a chance of powersteering out.

Yep, this is actually why AWD is (usually) better than 4WD, because it can drive the single axle, treating it as a 2WD.

Why would you try to slow down (with your brakes) while going downhill on a snowy road? That is the worst possible thing you could do. Go slower at the top of the hill or let off the gas to reduce your speed.

> AWD != 4x4. AWD + traction control absolutely helps driving on snow and ice with appropriate tyres.

Too late buddy. The way manufacturers abused AWD, 4WD and 4x4 terms they can mean anything now

Which manufacturer is using AWD incorrectly?

Dodge. They call their Charger implementation AWD, but it’s RWD only until a slip, then it engages the front axel.

They fooled me, and it drove like crap on snow. Always wanted to slide.

> All wheel drive helps zero with winter conditions, except for going uphill or some other acceleration-equivalent action

What are you on about? Living in Montana, AWD is dramatically better than 4WD. And winter tires are great. We never used them on one of our AWDs because the AWD is so dang good. Snow tires were absolutely required on our 4WD and 2WD cars. AWD or snow tires, I am mindful of stopping distance.

I will always choose AWD for the snow. Then add snow tires if needed.

Winter driving cover a broad range of conditions, from "I see snowflakes" to "are we still on a road?" Alleged "snow tires" that are good enough in the former can be next to useless in the later.

I helped an AWD SUV/crossover thing ten feet off the road a couple weeks ago. It was in very deep fluffy/dry snow, half on its side, sitting its weight on the snow rather than the tires. Only one wheel actually turned (front left). The AWD/TC system was literally out of its depth. 4WD, potentially with locking diffs, would not have had that problem. Once we pulled it enough to get some weight on the wheels, the AWD system kicked in and helped drive it back onto the road.

The guy had what he thought were snow tires (snowflake mountain symbol) but looking at the treads myself I didn't see the small grooves that imho are typical of proper snow tires. They looked like all seasons perhaps with some extra silicon to qualify for the badge.

If the weight of the vehicle is not on the wheels then locking diffs or snow tires won't help. If you are high centered you are high centered and you have to solve that problem first.

Typically, when you go off the road with some speed you will be high on the front but less so on the back. In this case we couldn't really tell as the rear wheels were not turning (AWD likely defaults to FWD for most driving conditions). In these cases I don't like digging around too much for fear that the car will settle/shift onto someone. We grabbed at the front bumper tow point, rotating the car 45* counterclockwise. At some point during this the rear axel decided to start helping and it half drove itself back onto the road.

Summer < summer + awd < good all season < good all season + awd < winter < winter + awd

Is my opinion from living in Michigan i.e. AWD is always a step up but rarely better than having the right tires. It depends a bit on the conditions too - are you looking out the window and wondering if your car will get stuck/make it up an incline or are you looking out the window wondering if your car is going to slide into a into a ditch/the car in front of you or is it an equal mix? AWD adds the most value when there was a heavy snow, unplowed roads, and relatively low traffic since. In any other case it’s really not all that helpful, except maybe a slippery uphill intersection but even then good tires help there and the inverse situation whereas AWD only helps in the one direction.

AWD or 4WD does nothing for you if you’re braking and trying to stop.

And snow tires do nothing if your two drive wheels are in an icy rut. Different solutions to different problems.

FWIW, in Michigan studded tires are illegal for on-road use in the Lower Peninsula. But they are legal in the Upper Peninsula.

That said, I strongly disagree with you about AWD. It makes a tremendous difference for control in general in all winter conditions. Adding snow tires to AWD and things are just excellent and way more predictable.

AWD really does nothing, it helps with acceleration but that is the easy part. The hard part is slowing down and all cars brake using all 4 wheels.

You don't brake better with an AWD car.

Well, except if you have learned to drive using 4 wheel slides like a rally driver. Then I sincerely hope you lose your license before your endangerment of others lead to an accident.

I used to drive a RWD BMW in the snow, and it seems lost on people that all cars have four wheel braking. All you need are decent snow tires.

> You don't brake better with an AWD car.

You engine brake better with an AWD car.

Even better with ABS brakes. You should never be that close to the limit, either way. Then you are already driving dangerously.

I never understood the opposition to good winter tires. Apart from the chore of shifting, and the added investment of an extra set of rims (usually), the cost of the tires isn't any larger over the long term. You wear two sets of tires interchangably so they last longer.

Storage here in the city can be costly if you don't have a suitable garage.

I always kept my winter tires in my typical 2x2x2m basement/attic storage belonging to the apartment. Storage would be $50/yr otherwise. I imagine it would be a lot more on Manhattan - but as a fraction of total rent it would probably be less!

> I never understood the opposition to good winter tires...

Hope-springs-eternal denial. And quite a few people don't figure that they'll stay with the same car (and/or live in the same climate) long enough for the "interchangeably so they last longer" thing to pay off.

> Apart from the chore of shifting, and the added investment of an extra set of rims [...]

The former is probably the biggest factor, with the latter taking care of the rest. All-season tires might be less-than-optimal tires in either summer or winter (though the higher-end ones have gotten much better), but the perceived convenience factor is a big enough selling point for most. And when their performance isn't sufficient in winter, people probably aren't going to immediately blame their all-season tires for a loss of traction. They'll just blame the weather and assume that "it is what it is," even with AWD.

If you've never driven on proper winter tires when the weather goes to shit, you don't even know what you're missing. But more than that, I think there's a huge segment of the car-buying public that doesn't give their tires any thought beyond "are they still good?"

Hell, my sister bought a Mercedes a couple years ago that happened to come from the factory with high-performance summer tires and no mention of that fact on the build sheet or window sticker (nor was it spec'd with large wheels with low-profile tires, where it'd at least some sense). Had I not looked at the sidewall when I was with her after the tire pressure sensor went off, she'd have been in for one hell of a dangerous surprise when the first winter storms hit a couple weeks later. Even the dealer was surprised by it.

Ever since then, I've always wondered just how many cars drive around in winter weather with the wrong tires and a blissfully unaware driver.

Double the cost? I thought about getting winter tires but my all season tires are rated for 60,000 miles or 6 years whichever comes first. I only drive like 6,000 miles per year so getting a second set of tires means buying 2 sets of tires every 6 years.

> I'd heard the folklore that snow tires are more important than all wheel drive for handling on both snow and ice, and having used them for a few years now, I'm a believer.

That seems obvious. AWD means you can use the traction of all tyres to move. But without snow tyres you have no traction, so AWD does nothing.

> So called "all season" tires are not snow tires.

Not quite true, there are 3PMSF all-season tyres, and unrated ASTs might behave well on snow, it depends on the compromises the manufacturer decided on, as the point of an ASF is to balance dry, wet, and snow. But where the manufacturer decides to put the balance is very relevant. That a tyre is all-season doesn't mean it's all-of-your-location-seasons.

In fact, you can have ASTs which are excellent in the snow and absolute shit on dry and wet, that's what "tyre reviews" found with the Tomket Allyear 3 (https://www.tyrereviews.com/Tyre/Tomket/Allyear-3.htm) for instance.

Also technically unrated "winter tyres" may not be suitable for snow either, they might be using better winterised compounds and deeper thread patterns but not sufficiently so to behave well on snow.

Every car is no wheel drive when there is enough slip

> So called "all season" tires are not snow tires.

Fun fact: US "all season" tyres are sold in EU as summer tyres.

You want to look into "all weather" tyres. The good one are rough equivalent to cheap winter tyre and decent summer tyre. It's still not worth it IMO if you're driving a lot but after COVID I drive little enough that I wouldn't get thru 2 sets of tyres before they rot away.

Just make sure you take them off in the summer. They go away really fast in warm weather.

It is not folklore. Take it from someone who lives in the actual north. My car doesnt see bare pavement for months. A two wheel drive car, with snow tires, will run rings around a 4x4 with summer tires. Chains are great, but have speed and distance limitations. We drive at 50mph/80kph on snow, on highways even faster. (Drive on snow every day and you get used to it.) No chain set will last long at such speeds. They are tools for short term issues like getting through a mountain pass.

A less understood aspect of snow tires is their flexibility in cold. A summer tire will stiffen up below -30. Park it overnight and it will have a flat spot the next morning. It will bounce the car until enough heat builds up in the tire for it to soften. The higher silicon content of proper winter tires prevents this.

This type of driving, except whitehorse is much warmer than where i am (our rivers/lakes remain frozen): https://youtu.be/a_hmPxBUZvc

Living in the upper Midwest here as well (Michigan) it's amazing how common the "you don't really need snow tires, you just need to know how to drive" is.

I drive pretty well, and getting snow tires made a huge difference in predictability. Braking is more consistent, acceleration is more consistent, and most importantly the point at which I lose traction when cornering is fairly consistent and predictable.

Yes, there's the overhead cost of a second set of wheels and TPMS sensors (because after a few years it's break-even with having the tires themselves swapped, and this way I can swap them myself when winter hits), but overall the cost isn't that significant because it offsets wear on my all-seasons. And it's so, so, so much better when it does snow. Or is icy. Or even is quite cold and just wet, because the tires are still flexible at temps when all seasons get quite hard and plasticky.

My ordering based on personal experience would be:

AWD + Winter > AWD + All-Season > FWD + Winter > FWD + All-Season

There are plenty of videos[1] showing the above. I guess it should come as no surprise that it comes down to the vehicle, the tires, the conditions, and the driver.

At least for me driving in the PNW (temps usually not too much below freezing), Kumho Crugens (all-season) on my AWD SUV are way superior to Michelin X-Ice (winter) on my FWD minivan. Braking is longer on snow and ice with all-seasons, so I leave 8 car lengths of distance minimum when following other cars. The SUV has superior ESC and traction control that way out perform the minivan.

Several times in my FWD minivan with winter tires, I have been unable to go uphill on icy roads and had to put on chains. Whereas the AWD has no issues at all.

[1] https://www.youtube.com/watch?v=bRYHlb61_9Q

> ... AWD + All-Season > FWD + Winter ...

> Braking is longer on snow and ice with all-seasons

I think braking performance is more important. I would choose FWD but on "proper" winter tires. It's better to risk not making up the icy hill, rather than to risk crashing into a front car or even injuring a pedestrian.

By the way, the video doesn't explore braking performance.

(For the unfamiliar with these TLAs: AWD - all-wheel drive, FWD - forward-wheel drive.)

Yup. I live in the mountains in Canada, have a FWD car with snow tires. Runs circles around trucks or SUVs with all-seasons.

I was a firefighter in a past life. These were installed on all our engines and trucks. They worked OK in snowy conditions up to an inch or so, then thy stopped having enough clearance to throw under the tire. We rarely used them and made sure to follow forecasts closely and chain half our equipment in anticipation. Anecdotally, these may work OK in areas where snow is not as common or often, but wind up next to useless where they might otherwise be considered helpful.

Do you have any thoughts about how they help with breaking? The "rotation of the wheel rotates the chain" makes me think they'll not help during breaking that much. They would probably slip from under the tire, and the next chain would not go under...

You aren’t stopping by slamming the breaks with chains, onspots, or neither. There will still need to be tire rotation to control direction. I don’t recall which was worse. Fact is snow and ice requires a lot more of everything to drive in. I stay home if I can these days.

These have been common in North America for large trucks operating in snowy places for decades - school buses, dump trucks, etc.

Handy because you don't have to stop/get out/interrupt service - just flip a switch and you've got improved traction!

I've seen them mostly on local (Boston area) fire trucks.

It seems like one of those things that's probably more common than you think, given that you'd have to pay very close attention and know what you're looking for to see them in use.

Also something I would never see living in Los Angeles.

However, living two hours away from LA in the San Bernardino mountains, our school buses were running these in the 80s and 90s.

as a large truck mechanic i can say theyre okay and degrade roads casually because operators suck at learning how to use them.. in real winters like Alberta the drivewheel is either frozen to the motorized arm all the time, or glides like a ballerina against a wall of ice from the tire. this is a solution for a problem of casual issue, like climate change in the south usa perhaps :)

They look like they would improve traction while moving, but when braking I could see the chains slipping out from under the tires letting the vehicle slide. Not fun on icy roads.

Seems like a great solution for light snow/mild ice but I would not want to trust my life to these in harsh conditions.

A school-bus or box truck that will basically get stuck everywhere if it doesn't have something under the driven axle. Braking is not what's limiting the conditions these vehicles can work in. Getting stuck because you stopped at a red light on a slight hill is more their problem which is what these chains solve.

Giving drivers a sense of control that doesn't match up with how the vehicle performs in braking looks like a pretty big design flaw to me.

These have been around for decades. Additionally, a lot of “braking” with these bigger trucks is “engine braking” like jake brakes, compression release, exhaust release, etc.

Can slow a lot by “simply” letting the jake engage.

We use them on our fire trucks, engines, tankers, etc, here in New England. Some of these apparatus way upwards of 30ton.

A two-wheel drive vehicle with an open differential is limited in acceleration by only one wheel (the drive wheel with the least traction). However, braking is always the combined effect of all wheels.

That's a fair question, though I would guess that, unless the wheel is locked, it is no more likely to slip out under braking traction than driving traction. That figure may well be higher than for fitted chains or studded tires.

AWD has the characteristic of improving driving traction while doing very little for braking or steering, as demonstrated by the guy who passed us and then rear-ended the mail delivery van.

In a true full-time AWD system when applying any power, there's half the torque which means there's more capacity for the tire to handle side loads from cornering/turning.

However, AWD in vehicles without traction control recovery from a slide is more difficult due to there being two different thrust vectors.

I take your point. I was thinking only of steering without drive traction.

These have been around since at least the 70s.

https://www.onspot.com/en-US/about-onspot---about-us/

patented on 1915, filed for patent at 1912

Was expecting Batman style chains that autonomously grapple onto the tires. These are not those.

What if a chainlink breaks and goes flying through someone's windshield? Seems like a major safety hazard.

The same concern also exists for traditional snow chains.

30% more traction sounds ... Really bad.

Aren't real snow chains more like 300% more traction in the right conditions, since regular tyres offer basically no traction?

“Up to 30%” as well!

Freaking cool, but maybe a slight projectile hazard?

Related question: If the alignment of the rotating discs goes out, can these chains turn into undercarriage destroyers?

Looks like the tires causes them to rotate, they don't have motors. So if they aren't aligned and the chains can't get under the under the tires, then they won't spin and hit the undercarriage.

You'd probably hear the rattling and stop driving

And rough on the pavement

Doesn't seem rougher than normal chains

Maybe slightly as the chain is slung under the tire so it's travelling faster than it would otherwise just being mounted onto the tire?

The chain gets compressed between the tire and the ground. It can’t really have a much different speed than the tire itself.

I was thinking about the initial swing in.

Possibly the opposite if they can be dis-engaged easily on sections without snow, where drivers would otherwise keep chains on

I live in Minnesota which gets plenty of snow, and chains are banned on public roads.

And likely beat the crap out of your undercarriage.

Do they make them for motorcyles?

This is the content I am looking for in 2023.

If you had them, and were about to fall over, would there be room to put a boot on the floor between those flails? Would you dare try it?

On the other hand, chances are it would make cars stay a safe distance away.

Was trying to find some reading material on these that addressed the question: what happens when large debris makes contact with the control arms for this? I've seen large chunks of ice that are dense enough and heavy enough to cause undercarriage damage.

Crazy coincidence with this post going live a few hours after I used tire chains for the first time.

These are already exciting, but the music really takes it to the next level.

Ads

Would be useless if the snow is actually deep ?

Yes, but then so would normal snow chains. These are meant for icy inclines, nothing else, really, but that’s the same as snow chains, only those take longer to put on and off.

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