a4Happy

I was just reading posts about this idea that a narrow tire is better in snow and ice than a wider tire, and I couldn't resist writing about this topic a little. I wanted to start a dialog about this topic and provide my opposing view point that I feel a narrow tire is not as good in snowy regions and you should be purchasing a wider tire, and see what everyone else's thoughts are on this? I also wanted to see if anyone can provide any real-world testing data that supports either argument? So, please keep this in mind when you read my (REALLY LONG) post...

A little background for me so you guys know I'm not just talking out of my rear about driving in snow. I grew up in Colorado driving in winter conditions, and I now live in Northern Lower Michigan, right in the snowbelt. I'm not saying we get the most amount of snow of all the places in the nation, but we do get our fair share. Our record snow fall was 186" for the season which happened three years ago, with our normal average being 148". It is not uncommon during the season for me to have 30" of snow at my house on the level (and I mean packed snow, after it has been blown around, compressed, etc.) I have driven my VW's and Audi's to and from work, 30 miles each way, 5 days a week, for 9 years now in these conditions on a winding back-country road. I started with the standard OEM tires on a front wheel drive Passat and quickly upgraded to snow tires, and then to a 4-Motion Passat, and then finally my Audi A4 Quattro. My first set of winter tires were Dunlop WinterSport M3's, and I'm now on to Nokian R's on my A4. I have driven in every kind of bad winter condition you can think of. Black ice, packed snow on top of ice, packed snow, slush, slush on top of packed, slush on top of ice, champagne powder, 3' snowdrifts that I've literally had to burst my way through to get to the other side, you name it and I've driven in it. In addition to this type of driving, I ride snowmobiles all winter long and I get the 'joy' of having to snowblow all this off my driveway with a 4' wide snowblower on a tractor, sometimes twice a day just so I can make it down my 750 foot long driveway.

So, all this being said, regardless of what "Tire Rack" and other industry professionals say, my butt on a snowmobile and my butt in my A4, and countless other vehicles with different tire widths and rubber compounds, says... this idea that a "narrow tire is better for snow" idea just doesn't make sense to me.

If you look at ANY motorized sport in the world, they typically run wider tires then a normal consumer vehicle, regardless of conditions (dry, rain, snow, etc.) Drag racing, Formula 1, NASCAR, CART, Indy, monster trucks, buggy's, snowmobiling, motocross, etc. are all examples of this. Why? Why is it that in motorized sports, the idea of a wider tire is good, but when driving daily, we think it's bad? Where is the testing to prove this? I've seen plenty of tests comparing a studded tire to non-studded, an all-weather tire to a snow tire, and one brand to the next, but NEVER a test of tire widths for winter driving. Yet somehow, this idea is out there that narrower is better! Who started this idea?!?

Regarding tire widths, I understand the idea that the weight of the vehicle, regardless of tire width, will produce the same square inch of rubber contacting the road, and therefore, there shouldn't be any difference with a wider tire in terms of contact patch. This said, for some reason, motorsports always seem to gravitate to a wider tire. Again, why? I also understand that a wider tire can dissipate heat faster, which at high speeds is critical, so maybe that's the reason? And of course there is a compromise between the width of the tire and the difficulty in physically turning the wheels due to weight (both rotationally and directionally) and as such, there is a balance between seeking more lateral grip and loosing out on something else like power or responsiveness to steering input. Either way, I find it interesting that we can point to countless sports where a wider tire or tread is used to provide more traction, yet for some reason we decide that on a standard car with your most precious cargo aboard, a narrower tire is somehow better for winter driving?

If this logic were true, then in theory, a bike with 1/2" wide tires (winter tread of course) should be better in the deep snow or ice than my car. After all, if narrower is better, then a bike tire is WAY more narrow then my car tire, let alone a snowmobile tread. The reality is, snowmobiles are incredible in snow, not mountain bikes. How can this be? A snowmobile has a 16" wide tread that is 136" to 150" long. That is WAY more rubber on the snow than a mountain bike! What this tells me, even without my years of driving experience, is that a wider tire would be better as it provides more rubber to contact the snow or stay on top of it, which means that each square inch of rubber has less weight and forces that it is responsible for stopping or moving, which is critical on a slippery surface.

The thought that a narrow tire and less rubber to grab the snow and ice somehow provides better traction just doesn't make any sense. I just sold my old snowmobiles and purchased new ones that had a larger tread on it so that I could have BETTER traction on the snow, not worse. And let me tell you, I get stuck about 1/10th as much with my new snowmobiles and their 144" long treads then I did with my old sleds and their 136” long treads. Imagine how much less I'd get stuck with a SnowCat and it's 14' wide tread!

As for going through slush... A wider tire means the tire manufacturer has more tread that they can design an appropriate pattern in to get through slush (if they even need to.) Along these lines, I've driven a Ford F-250 Super Duty with tires twice as wide as my A4's tires, going through slush on only one side of the car. In "theory" the truck should have pulled harder to the side with the slush because the tires couldn't "cut" through the slush as well as the thinner winter tires on my A4. Well guess what... In the Ford, I hardly noticed the slush at all. In my A4, it pulled more to the side with the slush. To what do we attribute this? Weight difference of the vehicles? Vehicle clearance? I mean honestly, if the "narrow is better" theory is true, then a truck tire that is TWICE as wide as mine, and not even a snow tire, should perform so horribly in the slush that the increased weight of the Ford should hardly be able to compensate for the horrible effects of the wide tire. Well, it didn't happen. The Ford hardly twinged, my Audi did (granted, once I was out of the slush I could kick the Ford's butt 10 ways to Sunday :-)

I have Nokian R's on my A4 right now, and next time I'm going to "buck the trend" and try to get as wide of a tire as I can. My current Nokian's are wider than what my Dunlop's were, and they are for sure performing better than the Dunlops. Of course, the Nokian is a true winter tire whereas the Dunlops were winter sport tires, so I attribute most of the improvement to better rubber and tread design then the width. But one thing is for sure, the wider Nokian's are going through slush BETTER than my thinner Dunlops were.

Lastly, I have found a few people here and there that have had similar thoughts to mine, and I find it most interesting that those that share my thoughts are usually from very snowy regions of the world. Here is one such tiny example of this... Jim Kerr, a writer for Canadian Driver that helps test winter tires every year, says "Wider tires provide more traction than narrower tires, but a narrow tire gets better fuel economy." http://www.canadiandriver.com/articles/jk/080604.htm. Now that is a quote I agree with.

Let the counter-points and fact bashing begin ;-) Again, point me to a test between tire widths instead of tire types if you know of one as I'd love to read it...

a4Happy

In continuing to do research, I found an interesting article with actual test results of the patch size of a wide tire vs. a narrow tire, from the same manufacturer, using different loads. Probably worth reading if anyone starts to discuss the amount of rubber touching the road on a wide tire vs. a narrow tire for the same vehicle.

http://www.performancesimulations.co...on-tires-1.htm

broadbandjim

Narrow will displace the snow better, no? I know that in my youth when I had a shortbox 4X4, we'd go 4 wheeling and invariably I'd end up pulling guys out clad with big mudder tires with my narrow OEM tires that looked like crap but that I was too broke to replace.

And since everything in life is a compromise, actual snow-covered travel being only occasional dictates having a tire that performs reasonably well in the dry as well as snow, so we pick a tire that is not too wide, not too thin.

a4Happy

Very true. In the winter time, I have also pulled out tons of trucks in a ditch that had wide tires. I've pulled out even more sedans that had wimpy little tires. The width issue by itself obviously isn't the entire argument, as it also depends on the tread compound.

I've also found that people with large "mudder" tires seem to have a tendency to think their rig is invicible, and they'll try things that will get their vehicle stuck more.

ChipB

It is inappropriate to compare the track width of a snow mobile to winter tires on your car - they are designed to operate in completely different ways! The snow mobile has a wide track to get grip on the snow surface, whereas a snow tire is designed to cut down through the snow to the road surface. I would agree that if you had your car out on the ski slope on top of 3 feet of snow base you'd probably be better off with wider tires - but that's not where one normally drives (at least, not on purpose).

Also, looking at fat tires on race cars is inappropriate to the discussion - yes, wider is better on the track, but when was the last time you saw NASCAR racing on a snow-covered track?

A skinnier tire will have higher pounds per square inch of load than would a wider tire - which helps the tire get to the road surface. But remember that everything is a compromise, and consequently there is no single right answer. Skinnier tires may get to the road surface better, but once there they would have less traction than would a fat tire that also gets to that same road surface. So fat tires work better in some conditions, but worse in others. So we compromse - make the tire a little skinnier, but not too skinny, and perhaps you hit the "sweet" spot of compromise beteen snow traction and road traction.

a4Happy

ChipB,

Great thoughts... Here's my rebuttle to them. The biggest argument for narrow tires *always* seems to be this notion of having more lbs/sq inch to try and push a tire's way through the snow to get to the road surface. Let me address this issue first.

If the temperatures are cold enough (ie. not hovering around 30-32 degrees), you will NEVER push packed snow aside to get to the asphalt. Who thinks this way? Honestly, have you ever tried to shovel that last 1" of packed snow your driveway with a shovel, one that has sharp edge on it? I'm talking the snow that was packed from your car driving on top of it a number of times because you didn't shovel it right away. The same snow that now has a nice gloss or shine to it and is as slick as ice? You basically have to take the sharp edge of shovel (a metal edge) and chip this hard packed snow away, or drop some salt on it to break it up overnight so you can chip away at it in the morning. Or, like me, get out a tractor with a bucket, put the bucket down at a hard angle and lift the front tires up, and then try to pry the snow up. What I'm trying to say is that hard packed snow is not easy to get through even with a shovel and a metal edge or even the bucket of a tractor.

So, where I live, packed snow on the roads is the norm. There is NO WAY a narrow tire is going to help bust through this snow to get to the road surface any better. I can understand this argument a *little* for those that live in region with sparatic snow, where you end up with slush, or lots of road travel that keeps it warm so it never freezes and gets packed down. However, don't we think that a tire designer would take this into consideration with their tread design? I purchased Hankook tires recently, partly because a major magazine tested them and found that they handled wet roads really well. Notice Car and Driver DIDN'T say "and if you're driving in wet conditions all the time, you need to down size the width of your tire." Instead, they did some testing of different tires with different tread patterns and determined which worked best to evacuate the water. Yet again, with winter driving, we just make this blanket statement that wide tires are bad, narrow tires are good. If I were a tire designer, I'm guessing I would cringe every time I heard this, as it would mean that I would now have less width in the tire with which to design a pattern that meets everyone's requirements. Basically, I just buy this argument, and you are correct, this is the exact reason a snowmobile has a wide track, to get as much traction on the snow as possible.

Regarding the comment about Nascar. Obvioulsy nascar doesn't run on a snow-covered track. The reason I feel this point is valid however is that the idea is the same, they are trying to get the tire to stick as much to the asphalt as possible. Asphalt, on a hot day, has a higher coeffecient of friction then on a cold day. A cold day probably has a higher coeffecient then on a wet hot day. A wet hot day more than a wet cold day, and so. Notice in ALL those scenarios of a reduction in the coeffecient of friction of the road, that they don't downsize the width of the tire. Instead, they bring out the wet tires with a tread pattern used to evacuate the water as fast as possible. Snow is nothing more than a road condition with a very low coeffecient of friction, so why do we feel that putting less rubber on it means we'll get more traction.

Long story short, I agree with your comment that for years people have tried to hit the "sweet" spot of compromise. But here's my issue, why do *WE* think a narrow tire is one end of the compromise? Wouldn't it be better to just ditch this idea and instead let the tire manufactures put their best foot foward, in whatever size they feel is best?

cb22

Registered for this site just to comment..

I've read your opinion and argument for wider being better on snow and I laughed a bit when you mentioned...

"If you look at ANY motorized sport in the world, they typically run wider tires then a normal consumer vehicle, regardless of conditions (dry, rain, snow, etc.) Drag racing, Formula 1, NASCAR, CART, Indy, monster trucks, buggy's, snowmobiling, motocross, etc. are all examples of this."

Have you ever watched or seen the IRC (International Rally Championship) ??? Most of those guys...*cough*, professionals run between 165 and 185s on their cars for snow conditions. More PSI on the ground is KEY! Fat tires running a low PSI are good in DEEP fresh snow. They everyday driver with a vehicle that has a "light" GVWR needs the skinny tire to put more weight on the road.

a4Happy

Score one for the narrow tires. Great example. Would the courses they run on be an example of the type of conditions we'd find on our roads throughout a winter season? Ie. are they running on asphalt or dirt? With lots of racers traveling over the race course, does the course get packed down or turn to mush? If more PSI is key, why do they stop at 165, why not go even thinner? (half joking here, 165 is pretty thin.) Do they typically run with studded or non-studded tires?

Either way, glad you joined the forums if for no other reason than to post a comment.

cb22

Check out these guys in Norway and notice skinny tires! Amazing how fast they can go on snow and ice!

http://www.youtube.com/watch?v=RBXB5...eature=related

kleinbus

It truly depends what car owner is after...

Looks? Traction? and so on...

+2 for narrower if you want winter traction.

Simple equation is the square area of contact patch tire touches the road.

Sure this wider-better works down south and warm where most of people seems to live, but I grew up at Arctic Circle levels and most common width with studdless or studded pure winter tire was 195 or 205 on VW Passat size cars.

Wider is worst at lush as the mess does not get out from grooves. Hands on experience. I drove two different 80ft long / 120k lbs truck trailer combination on very same day on pretty same conditions and vehicles were equipped with transportation industry winter tires (slushy down south and snow/ice hours later up north), one was with "super singles" and other one was with normal dual wheels. No matter of the truck weight, the super single trailer got into slush slide at slower speeds than the one with dual wheels.

No matter I learned car and semitrailer driving in conditions where roads stay white, snowy and icy whole winter season and we don't use chains like here in States, you don't need to believe me, just go and check those WRC winter tires, sure those are extremes with not just studds, those are monstorous spikes, but anyways, the tire itself is so narrow that it looks like bicycle tire on normal car. Though those tires have temperature limit and have to be driven on snow and ice all the time as otherwise they overheat and spikes will begin to get loose and come off. Few times they had to cancel the races when there wasn't enough snow and was too warm for those winter racing tires...

My winter set with Blizzaks are same size as my summer 235/60 R18. Why I don't have narrower? There was no other size available for 18x8" rims, 17" and 16" had options but I chose to keep org size rims.

Let's approach this from other direction...

Summer: Wider allows more rubber to contact the pavement but temperature haves huge effect as cold tire slids around the track while warm tire and warm track is the key for taction.

Rain: Wider gets hydroplanning earlier than "normal" or narrow. Even F1 rain tires are narrower than normal dry tire and with rain tires they slow down, the speeds are lower than with dry tires as there is no traction and rain tires have speed limit.

Winter: With wider tire, vehicle mass is devided to larger contact area that gives less traction than narrower on normal driving contition (going off-roading wider is better but that is another story).