Why your SUV sucks in the mountains

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Originally Posted by jamal

Brake bias used to be done with a proportioning valve. The way they work is that equal pressure is sent to front and rear up to a certain point determined by the valve. After that, rear pressure is lower because under hard braking you transfer weight forward and the fronts do more work. More modern cars just let the abs figure out out. Either way, with low traction and braking forces the brakes will be well below the range where the biasing occurs. However, the actual brake torques at the wheels are not 50:50 because the rotors and caliper piston area are bigger up front. Generally, it's about a 70:30 ratio. For the best performance, you want the brake forces to match the weight distribution. With low traction, low braking forces and very little weight transfer, that's going to wind up being pretty forward biased. The reason for that is because you don't ever want the rear brakes to lockup first.

On a truck with rear drums and maybe no or not great abs, being in 4wd is definitely going to make a difference as shown in the videos. I don't imagine there is much difference in how abs and brake biasing works between more recent cars and trucks, but an SUV probably has closer to 50:50 weight distribution than a fwd car, so the brakes just never provide enough force at lower speeds.

I'd like to see a followup using a subaru or something with and without the awd engaged (automatics generally have a fuse holder to disable the transfer clutches), I'm not sure you would get much of a difference. Plus those clutches tend to be more open under braking.

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Thanks for chiming in. As usual, I learn tons from your posts on cars, esp Subies.

Thanksgiving anecdote.
My B-I-L is spouting off that the Cherokee was better than the X5 in the snow last winter. I asked what tires he had on the X5. "I don't know." Well then I asked if he bought it with the M-Sport package or the one of the summer tire packages or options. "I don't know."
Well, I said that the Cherokee doesn't even come with a summer tire option, so big wide summer tires are of course going to perform worse in snow than the skinnier all-seasons on the Cherokee.
"Well all I know is that Mrs. B-I-L couldn't get down the alley with the X5."

This is a classic

https://www.youtube.com/watch?v=CuTXUcoGdhw

AWD Stick shift BMW wagon with performance winters works great in rain and snow. RWD bias to do donuts the front wheel traction to straighten out.

Snow tires on Corolla - CHP/CSP/etc: “Sorry, chain law is in effect. You’ll need to put on chains or you’re not going through.”

Summer tires on dumb CUV with AWD - “Go ahead. Be safe up there.”

The reasons to have AWD/4WD aren’t always based in fact, but they are rooted in reality.


Sent from my iPad using Tapatalk

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Originally Posted by XXX-er

yeah but he is british and they can't drive

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That's funny from an Asian guy.

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Snow tires on Corolla - CHP/CSP/etc: “Sorry, chain law is in effect. You’ll need to put on chains or you’re not going through.”

Summer tires on dumb CUV with AWD - “Go ahead. Be safe up there.”

The reasons to have AWD/4WD aren’t always based in fact, but they are rooted in reality.

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I get your point, but they will check for the M&S logo on the tires, and summer tires don't have that.

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Originally Posted by I've seen black diamonds!

AWD with all season tires will often get you up a slick hill better than FWD with snows. I suspect some folks experience this and think, "I didn't get stuck! I don't need snow tires." Somehow fear of getting stuck is more prominent than fear of not stopping.

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Um, no, your first sentence is not correct. Simply put, the device that provides traction to a vehicle are the tires that contact the surface. All season tires don't have the same traction as a winter tire. It doesn't matter the drive train, it matters what rubber meets the road. But the second sentence is probably what gets people driving an AWD vehicle into trouble with all season tires. Probably gets them into trouble with snow tires too, because I'm still amazed when travelling in the mountains how fast people drive on compact snow and ice. They must think those studded tires are going to stop them just as fast if they were on dry pavement.

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Originally Posted by Toddball

What about tires with macho tread but all-season rubber? Doing the snows + steel wheels vs. new M+S now. M+S were fine on my AWD wagon last year but it's time to replace them.

Specifically thinking about Yokohama Geolandars right now, if anyone has opinions on those.
https://www.tirerack.com/tires/tires...cleSearch=true

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You'd be okay the first season on a set of these. Just know that they aren't going to perform as well in cold conditions, below 32F like a true winter tire will. If you've got worn winter tires and looking to replace with the Yoko's, you will still eventually should look to get a set of winter tires after about 12k miles on the Yoko's.

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Originally Posted by Toadman

It doesn't matter the drive train, it matters what rubber meets the road.

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Simply put, you might be oversimplifying things.

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Originally Posted by Toadman

Um, no, your first sentence is not correct. Simply put, the device that provides traction to a vehicle are the tires that contact the surface. All season tires don't have the same traction as a winter tire. It doesn't matter the drive train, it matters what rubber meets the road. But the second sentence is probably what gets people driving an AWD vehicle into trouble with all season tires. Probably gets them into trouble with snow tires too, because I'm still amazed when travelling in the mountains how fast people drive on compact snow and ice. They must think those studded tires are going to stop them just as fast if they were on dry pavement.

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Waaaaaaaaay too many variables for the first assumption.
My Honda Odyssey, FWD, can't get up my driveway with studded snows, but 3 different AWD cars with all-seasons can get up it.

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Originally Posted by Toadman

Um, no, your first sentence is not correct. Simply put, the device that provides traction to a vehicle are the tires that contact the surface. All season tires don't have the same traction as a winter tire. It doesn't matter the drive train, it matters what rubber meets the road. But the second sentence is probably what gets people driving an AWD vehicle into trouble with all season tires. Probably gets them into trouble with snow tires too, because I'm still amazed when travelling in the mountains how fast people drive on compact snow and ice. They must think those studded tires are going to stop them just as fast if they were on dry pavement.

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If we were all standing at the bottom of a snow covered hill I'd put my money on the AWD with all seasons. He has power to all 4 and isn't dragging the rolling resistance of two tires, even if those all seasons only offer half the traction it'll still do better. Presumably they'll have to come back down at some point though in which case I'd probably take the FWD with snows.

Yup. I've even tried backing up the drive with the Odyssey, and it just won't do it, the curve at the crux defeats it. With their stupid nanny system on or off.

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Originally Posted by PNWbrit

That's funny from an Asian guy.

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hybrid AZN actualy or hAZN

but AZN, EI it doesnt matter once you live up here you gotta buy the right equipmnet and get to work or you lose the job

A fresh new pair of all-season tires are better than nearly end of life snow tires.

It's really all about tread depth. People hang on to tires waaay too long. That wear line you see... don't take it all the way to that if you drive in snow.

"Good drivers with all-season tires are 469% less likely to cause congestion and accidents than your pussy ass neighbor who has snow tires and drives like Grandma!"
-Me

This thread should be titled "Why your all-season/summer tires suck in the mountains in the winter"

I have an SUV with studded Hakkapeliittas and it does not suck in the mountains.

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Originally Posted by Toadman

Um, no, your first sentence is not correct. Simply put, the device that provides traction to a vehicle are the tires that contact the surface. All season tires don't have the same traction as a winter tire. It doesn't matter the drive train, it matters what rubber meets the road.

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But, if less force at each wheel is needed to get the car moving (say it takes 800lbs of total force to move the car, then its 200lbs at all 4 wheels vs 400lbs at each wheel on a 2wd car), then the friction force at each wheel can be lower with a 4wd. How much that friction force(coefficient) is increased by the winter tires siping/rubber would be interesting to measure as it might make up the difference. IDK.

Regardless, people drive way too damn fast for the conditions all the damn time.


Lastly, the BIG thing everyone is overlooking is that your average 4WD SUV is one helluva lot safer purely because of its mass and height. I am confident that i will be fine driving in shitty conditions, and if shit does go wrong it will likely be at slower speeds where and impact will only hurt my wallet (going off the edge of a cliff excepted). But the other folks on the road scare the shit out of me, and when/if they crash into me, i want to be in the big vehicle every damn time.

I have never gotten an AWD/4WD SUV with snow tires stuck**.

I have gotten trucks stuck*, the weight distribution is terrible. Even with 4wd and snow tires. (even with DURATRACS, omg.) To make a truck work really well you need to put at least 500lbs over the rear axle. Which is essentially what all the glass and metal of an SUV provides. Diesel trucks can be even worse with the extremely heavy motor up front and the long length. Trucks tend to slide sideways often times it seems. I've found 1/2 ton trucks to be better than 3/4 or 1 tons for some reason, I think it's the more supple suspension and less unsprung weight.

I have gotten AWD cars with snow tires stuck*. They normally have great traction but not enough ground clearance. If you stop in the wrong spot you can sink up to frame really quick.

I have never owned a FWD car but snow tires or not that seems to be normally what I've seen stuck*. When traction is low, the "one tire fire" becomes the norm. Couple with poor ground clearance and generally very overbearing traction control you get stuck* very easily.

*My definition of "stuck": can't make forward or rearward momentum in a relatively level/benign situation after coming to a full stop and requires at least a push or a small tug from another vehicle to get moving. Yes, if you have a really aggressive driving style and use momentum to get up hills and such you can get around with a FWD with snows. But I'm talking about coming to a full stop in say a ski area parking lot with a slight incline and 3-4" new snow on a packed snow base.

**in normal driving conditions. Not the "I'm going to bust through that 4' tall snowbank" or "see if i make it up that road that hasn't plowed all winter" stuff. In that case, I have been stuck lots. :fmicon:

So basically you should buy an Audi All-Road Diesel with a 6-speed MT or a Land Cruiser.

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Originally Posted by californiagrown

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Lastly, the BIG thing everyone is overlooking is that your average 4WD SUV is one helluva lot safer purely because of its mass and height. .

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The acident you are not in is safer so ^^thats rong cuz SUV's all have high CG/short WB which means when they start the wigwag at highway speed they end up in the ditch

After a good snow fall or even just a wet road that has froze to glare ice as the arctic front moved south it was not unusal to see a couple of upside down SUV on hy 97 in northern BC

an ex cab pickup is always more stable cuz the WB is another 18 " longer and IME there was a lot less drama in a Mini van or small front wheel drive BECAUSE of the lower CG

the short WB of an SUV is good for navigating strip malls and distancing oneself from being a mini van person

Tirerack has done a bit of testing. Here's all seasons vs winter
https://www.tirerack.com/tires/tests...y.jsp?ttid=103

Stopping distance from 30mph is 59ft on winters, 89ft on all seasons. That works out to coefficients of friction (µ) of 0.34 and 0.51 respectively (actually they would need to be a bit higher to generate those stopping distances in the real world). A good summer tire on pavement can have a cf of 1.0 or more.

Here's winter, a/s, and summer on an ice rink
https://www.youtube.com/watch?v=GlYEMH10Z4s

stopping distance from 10mph is 21ft on winters (µ = 0.15), 39ft on all seasons (µ = 0.08). Extrapolate to 30mph and you get stopping distances of 200 ft for winter tires, and 376ft on all seasons. That's a long ass way- over a football field to stop from 30mph. On dry pavement you can do that in like 35ft.

What you might be able to take from that is that on snow, the winter tire has about 50% more grip. That means that from an accelerating and driving up a hill standpoint, in snow, an awd/4wd is going to have an advantage on the worse tires.

On ice though, the winter tires have nearly twice the grip. The tread pattern and depth is irrelevant in this case and the extra grip from the winter tires comes mostly from the rubber compound itself, which is much softer. If you haven't handled a blizzak, it's worth wandering into a firestone store or something and shoving your thumb into the tread to feel how soft it is. That very soft rubber, plus the siping, allows the tread to deform and provide lots of very tiny biting edges as well as having a higher µ. I'm fairly certain that bridgestone even claims better traction on ice with blizzaks than the studded winterforce.

Anyway, if you drive in snow on a regular basis I don't know why you would willfully choose to have 1/2 to 3/4 less traction. Once you have actually driven on snow tires you really won't want to be out on anything else.



E: more data:
https://www.tirerack.com/tires/tests...y.jsp?ttid=167
https://www.caranddriver.com/feature...ce-data-page-3

both generate in the ballpark of 0.15g stopping on ice, but only around 0.25 on snow.

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Originally Posted by Leavenworth Skier

I have never gotten an AWD/4WD SUV with snow tires stuck**.

I have gotten trucks stuck*, the weight distribution is terrible. Even with 4wd and snow tires. (even with DURATRACS, omg.) To make a truck work really well you need to put at least 500lbs over the rear axle. Which is essentially what all the glass and metal of an SUV provides. Diesel trucks can be even worse with the extremely heavy motor up front and the long length. Trucks tend to slide sideways often times it seems. I've found 1/2 ton trucks to be better than 3/4 or 1 tons for some reason, I think it's the more supple suspension and less unsprung weight.

I have gotten AWD cars with snow tires stuck*. They normally have great traction but not enough ground clearance. If you stop in the wrong spot you can sink up to frame really quick.

I have never owned a FWD car but snow tires or not that seems to be normally what I've seen stuck*. When traction is low, the "one tire fire" becomes the norm. Couple with poor ground clearance and generally very overbearing traction control you get stuck* very easily.

*My definition of "stuck": can't make forward or rearward momentum in a relatively level/benign situation after coming to a full stop and requires at least a push or a small tug from another vehicle to get moving. Yes, if you have a really aggressive driving style and use momentum to get up hills and such you can get around with a FWD with snows. But I'm talking about coming to a full stop in say a ski area parking lot with a slight incline and 3-4" new snow on a packed snow base.

**in normal driving conditions. Not the "I'm going to bust through that 4' tall snowbank" or "see if i make it up that road that hasn't plowed all winter" stuff. In that case, I have been stuck lots. :fmicon:

So basically you should buy an Audi All-Road Diesel with a 6-speed MT or a Land Cruiser.

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Mostly true regarding trucks however a 1 ton diesel 4wd with decent tires is going to get you through a lot more than any car/suv (excursion excepted). stopping while going around a curve or on an off camber road? Not so great. Powering up hill or keeping it straight when you hit a slushy patch on the highway that would pull smaller cars and trigger a spin out? The perfect machine. It's a tool that does some things great and others not so great, just like any other vehicle out there. Know what you have an what it's limitations are and you'll be set. 90% of the time I drive my 4 door long bed Cummins into the mountains, I know it'll handle anything I can throw at it like a champ as long as I'm using the go peddle, when it comes time to use the slow peddle I know it's time to back off and take it really easy. Trucks do like to get loose in the back but keep in mind that they need to travel a long way before you actually loose control which means they usually straighten themselves back up, or are at least pretty easy to straighten up. Further evidence that the driver plays a bigger role than the vehicle or tires....I usually pull out about a half dozen people each year in various forms of cars/suvs with a various selection of tires but have never had my truck pulled out. And that's with decent all seasons, not snows on the truck. My Subaru was better overall on the highway but I did get it stuck in a wind drift once due to limited ground clearance (I gave it all I had to get through too) and it would get pulled by deep or slushy snow.

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Originally Posted by XXX-er

The acident you are not in is safer so ^^thats rong cuz SUV's all have high CG/short WB which means when they start the wigwag at highway speed they end up in the ditch

After a good snow fall or even just a wet road that has froze to glare ice as the arctic front moved south it was not unusal to see a couple of upside down SUV on hy 97 in northern BC

an ex cab pickup is always more stable cuz the WB is another 18 " longer and IME there was a lot less drama in a Mini van or small front wheel drive BECAUSE of the lower CG

the short WB of an SUV is good for navigating strip malls and distancing oneself from being a mini van person

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Sure, short wheel bases hurt (see my comment about trucks above) but not all SUVs have short wheel bases, many are longer than cars, and the COG doesn't make it less stable on ice. It'll be more likely to roll once the tires get traction but when there is no traction it won't make fuck all of a difference. I suspect your experience on Hy97 would correlate more with a false sense of security.

I luv me sum snow tires.

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Originally Posted by GPP33

. . . a 1 ton diesel 4wd with decent tires is going to get you through a lot more than any car/suv (excursion excepted). stopping while going around a curve or on an off camber road? Not so great. Powering up hill or keeping it straight when you hit a slushy patch on the highway that would pull smaller cars and trigger a spin out? The perfect machine. It's a tool that does some things great and others not so great, just like any other vehicle out there.

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gun rack and MAGA sticker optional

what bums me out the most is when the windy mtn highway by me is relatively crowded and slick and somebody in their vehicle loses traction in a cambered turn or sidesloped section of pavement and they start sliding, spinning their wheels, and slowly spinning. it generally leads to many other vehicles having the same problem and becomes a slow motion goat rodeo that often results in an unfortunate change of plans and expectations for me and my passengers.

my experience with FWD and snow tires in the tahoe area and sierra foothills has been overall positive. cornering and braking are noticeably improved on slick roads (of course). I have evaded involvement in the above described goat rodeo with this set-up by gingerly weaving my way through (it's not always possible to get around it). a few times, i have almost gotten stuck on very slick inclines starting at a stop with the FWD snow tire set-up. my fwd vehicles have always had decals to evade caltrans. the old "4wd" nissan altima was super fun to drive on the snowy slick pavement.

CHP's in the foothills still include rwd patrol cruisers with modern studded snow tires in their winter fleet.

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Originally Posted by GeezerSteve

gun rack and MAGA sticker optional

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But truck nuts are not.

My Forester with WRG3s was a great combo for here in California. Were solid in the snowy mountain roads and wore surprisingly well overall as a year-round tire. Did notice that they didn't perform as well as dedicated snow tires on ice, but it's to be expected and I knew that going in. However, they essentially performed like a snow tire.

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Originally Posted by bodywhomper

goat rodeo

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heh. I'm going to have to start using this

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Originally Posted by GeezerSteve

gun rack and MAGA sticker optional

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As long as Trump keeps on keeping tele alive I’ll sport a MAGA sticker!

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Originally Posted by plugboots

I get your point, but they will check for the M&S logo on the tires, and summer tires don't have that.

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M&S means all season tires, not snows. Better tread for snow than summer tires but don't have the soft rubber. True snows have the snowflake symbol. Good luck getting the guys checking tires to pick that out. Took me 10 minutes to find the symbol on my new X-Ices.

Anyone old enough to have switched from old climbing shoes to sticky shoes knows the difference different kinds of rubber can make.

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Originally Posted by Toadman

Um, no, your first sentence is not correct. Simply put, the device that provides traction to a vehicle are the tires that contact the surface. All season tires don't have the same traction as a winter tire. It doesn't matter the drive train, it matters what rubber meets the road. But the second sentence is probably what gets people driving an AWD vehicle into trouble with all season tires. Probably gets them into trouble with snow tires too, because I'm still amazed when travelling in the mountains how fast people drive on compact snow and ice. They must think those studded tires are going to stop them just as fast if they were on dry pavement.

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The same can be said for how lots of people ski--lots of people think that because they can go fast they can turn and stop fast.

Was at June lake pulling into hotel lot. Made it through all kinds of crazy over the pass. Last 50 feet into hotel lot car stalled and I went into snow bank. Almost went into the hotel pool and it was good I ended in bank. We were so tired but had to dig car out. Could not get traction on slope and it took a while. Skied pow for a few days and headed home. Immediately bought true snows to replace AS and it worth every penny. But I get the expense side. Problem is once you slide it’s too late.

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Originally Posted by whyturn

But I get the expense side.

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Don't you have like 10 pairs of pow skis, though?

Going narrow on your snows really helps with directional stability, not dragging if you are crossing lanes in the slush, and generally keeping rubber on the asphalt. Huge difference in positive control. Especially helpful if you upsize your summer tires for off road.

4runner with 275 section width at (265 stock) but 245 snows! Subaru 225 stock and 215 snows! Huge performance gains to be had...

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Originally Posted by Summit

Going narrow on your snows really helps with directional stability, not dragging if you are crossing lanes in the slush, and generally keeping rubber on the asphalt. Huge difference in positive control. Especially helpful if you upsize your summer tires for off road.

4runner with 275 section width at (265 stock) but 245 snows! Subaru 225 stock and 215 snows! Huge performance gains to be had...

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Yeah.

It's really too bad tire mfgs don't know that people would love to do that without downsizing the overall diameter. It's hard to find tires with an aspect ratio >65. I'd love to go 215/70 for the Outback -- gets you an extra half inch of GC over the 215/65, which matters in deep snow.

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Originally Posted by whyturn

Problem is once you slide it’s too late.

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You need a new pit crew

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Originally Posted by old goat

M&S means all season tires, not snows. Better tread for snow than summer tires but don't have the soft rubber.

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Well exactly. That was my point. All-seasons are way better than summer tires in cold and snow, and I was making that distinction. At the change checkpoint heading up to Tahoe on 80 they definitely look for that logo.

Very very few people actually buy summer tires - sports cars and sport sedans/coupes, that's it. They're more expensive and wear faster than all seasons, and unless you are a driving enthusiast, you don't pick those for a daily driver.

Which is why the comparisons between winter and summer tires are bullshit. And within the large world of all seasons, there are ones that will work pretty well in occasional snow (anything newer - with deeper tread - and in the touring or grand touring categories), and others that won't work so well (anything older - with low tread - and the ones more towards the performance end of AS tires, like UHP category, that may have more performance oriented rubber compounds that are harder in cold temperatures).

This is also why pretty much any all terrain tire works pretty well on any AWD or 4WD SUV/ CUV/ truck, so long as it has deeper tread and reasonable siping. That's a perfectly decent vehicle + tire for winter use for those who see occasional snow, like driving up to ski from somewhere that is mostly dry (not covered in snow) in winter.

True winter tires are definitely an improvement in snow. Whether they're worth it depends on the vehicle and where you are going to drive it regularly.

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Originally Posted by jamal

Tirerack has done a bit of testing. Here's all seasons vs winter
https://www.tirerack.com/tires/tests...y.jsp?ttid=103

Stopping distance from 30mph is 59ft on winters, 89ft on all seasons. That works out to coefficients of friction (µ) of 0.34 and 0.51 respectively (actually they would need to be a bit higher to generate those stopping distances in the real world). A good summer tire on pavement can have a cf of 1.0 or more.

Here's winter, a/s, and summer on an ice rink
https://www.youtube.com/watch?v=GlYEMH10Z4s

stopping distance from 10mph is 21ft on winters (µ = 0.15), 39ft on all seasons (µ = 0.08). Extrapolate to 30mph and you get stopping distances of 200 ft for winter tires, and 376ft on all seasons. That's a long ass way- over a football field to stop from 30mph. On dry pavement you can do that in like 35ft.

What you might be able to take from that is that on snow, the winter tire has about 50% more grip. That means that from an accelerating and driving up a hill standpoint, in snow, an awd/4wd is going to have an advantage on the worse tires.

On ice though, the winter tires have nearly twice the grip. The tread pattern and depth is irrelevant in this case and the extra grip from the winter tires comes mostly from the rubber compound itself, which is much softer. If you haven't handled a blizzak, it's worth wandering into a firestone store or something and shoving your thumb into the tread to feel how soft it is. That very soft rubber, plus the siping, allows the tread to deform and provide lots of very tiny biting edges as well as having a higher µ. I'm fairly certain that bridgestone even claims better traction on ice with blizzaks than the studded winterforce.

Anyway, if you drive in snow on a regular basis I don't know why you would willfully choose to have 1/2 to 3/4 less traction. Once you have actually driven on snow tires you really won't want to be out on anything else.



E: more data:
https://www.tirerack.com/tires/tests...y.jsp?ttid=167
https://www.caranddriver.com/feature...ce-data-page-3

both generate in the ballpark of 0.15g stopping on ice, but only around 0.25 on snow.

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Boom.

Please recall this post when discussing all-seasons vs snows, all ye tire jongs.

I forgot there was even such a thing as summer tires.

I don’t even bother taking the blizzaks off for the 2 non snow months of july and august here lol

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Originally Posted by jamal

Tirerack has done a bit of testing. Here's all seasons vs winter
https://www.tirerack.com/tires/tests...y.jsp?ttid=103

Stopping distance from 30mph is 59ft on winters, 89ft on all seasons. That works out to coefficients of friction (µ) of 0.34 and 0.51 respectively (actually they would need to be a bit higher to generate those stopping distances in the real world). A good summer tire on pavement can have a cf of 1.0 or more.

Here's winter, a/s, and summer on an ice rink
https://www.youtube.com/watch?v=GlYEMH10Z4s

stopping distance from 10mph is 21ft on winters (µ = 0.15), 39ft on all seasons (µ = 0.08). Extrapolate to 30mph and you get stopping distances of 200 ft for winter tires, and 376ft on all seasons. That's a long ass way- over a football field to stop from 30mph. On dry pavement you can do that in like 35ft.

What you might be able to take from that is that on snow, the winter tire has about 50% more grip. That means that from an accelerating and driving up a hill standpoint, in snow, an awd/4wd is going to have an advantage on the worse tires.

On ice though, the winter tires have nearly twice the grip. The tread pattern and depth is irrelevant in this case and the extra grip from the winter tires comes mostly from the rubber compound itself, which is much softer. If you haven't handled a blizzak, it's worth wandering into a firestone store or something and shoving your thumb into the tread to feel how soft it is. That very soft rubber, plus the siping, allows the tread to deform and provide lots of very tiny biting edges as well as having a higher µ. I'm fairly certain that bridgestone even claims better traction on ice with blizzaks than the studded winterforce.

Anyway, if you drive in snow on a regular basis I don't know why you would willfully choose to have 1/2 to 3/4 less traction. Once you have actually driven on snow tires you really won't want to be out on anything else.



E: more data:
https://www.tirerack.com/tires/tests...y.jsp?ttid=167
https://www.caranddriver.com/feature...ce-data-page-3

both generate in the ballpark of 0.15g stopping on ice, but only around 0.25 on snow.

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Best post in here. Thank you!

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Originally Posted by old goat

M&S means all season tires, not snows. Better tread for snow than summer tires but don't have the soft rubber. True snows have the snowflake symbol. Good luck getting the guys checking tires to pick that out. Took me 10 minutes to find the symbol on my new X-Ices.

Anyone old enough to have switched from old climbing shoes to sticky shoes knows the difference different kinds of rubber can make.

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M&S doesn't really mean shit. Tire companies are generally pretty responsible about the use of M&S but don't take it at face value. I have BFG KM2s on my jeep (they get the M&S designation) which actually have less traction than my daughters saucer sled on packed snow. I'm talking fucking scary how little traction they have. I'm pretty sure in the 10mph ice braking test Jamal linked above they simply wouldn't stop, ever.