My AWD vehicle slips and slides in the snow. What am I doing wrong?

This stems from the SUV vs. minivan thread, but I didn’t want to hijack it.

I bought an AWD car (a Subaru) because I hate slipping and sliding in the snow. Fortunately, where I live doesn’t get all that much snow, but 5-10 times a year, I’ll have to drive on somewhat poorly plowed streets.

Here’s the problem: on two different occasions during winters, I’ve come up to a stop sign in maybe an inch or a half-inch of snow, and press the brakes, and nothing happens (besides barreling right through the stop sign). I’ve been very lucky that on both occasions, there was nobody else in the intersection, otherwise I could easily have been T-boned or T-boned someone else. I use all-season tires since I don’t have the space to store 4 spare tires and I assume it’s a bit pricey to get them taken off and on twice a year every year. As I said, I only need the traction a handful of times during the year.

Are snow tires my only option? Do snow tires help braking or just the acceleration?

AWD only helps you* go* in the snow, not stop. Slow down, and give yourself enough lead time to stop gradually.

Remember, AWD doesn’t help your braking at all!

Snow tires will help your braking and overall handling. So will driving a lot more slowly when you know the weather is bad.

Snow tires are also not meant exclusively for the snow. They also have better cold weather characteristics versus all-season.

All told, I prefer to slow down and be cautious rather than change my tires, even with Michigan’s weather.

as already posted, slow down sooner and over a much larger time frame. most drivers already brake to late under dry conditions but wet or snow means you need larger stopping distances

First of all, while all wheel drive may help you gain motive traction during acceleration and may (depending on the system) help maintain neutral steering in cornering, it has essentially no effect on braking capability. All cars have brakes on all four wheels. Your Subaru should have anti-lock disc brakes all the way around, which helps prevent the brakes from locking into a skid by pumping the brakes at ten or more cycles a second (allowing the wheels to “roll” slightly and then brake, which has a higher coefficient of friction than continuous braking); however, if there is no traction between the tires and the street, there is no braking force, period. The assumption that all wheel drive will give you traction in all conditions is a misnomer that has led to innumerable accidents, especially on ice, snow, and unsealed dirt roads; the latter is the most common cause of accidents in Central and South Africa by aid organization employees driving AWD Land Cruisers as if they are driving around town in a Jaguar coupe, according to a professional offroad and evasive driving instructor I talked to a few years back. Or, as the Audi manual I read a couple years ago said at the end of the quattro all wheel drive system section, “The laws of physics still apply!”

As for the specific conditions; 1/2 to 1 inch of fresh snow on pavement is about the worst driving conditions next to ice and hardpack; it is just enough to create a crust of snowflakes suspended on a low viscosity liquid layer that is kept just above melting by the macadam of street pavement. Salting roads during snowfall can actually make this worse, as the layer will stay liquid at lower temperatures. You’ve basically surfing on top of the layer–like hydroplaning on rainwater, but even worse–until you slow to a crawl. If you’re sliding around in these conditions and going right through intersections, you are going way, way too fast for the conditions, and need to slow down or just not drive until the snow melts or is cleared.

Regarding tires: there is a wide range of capability in “all-season tires”, from basically just slightly better than summer use high performance to “suitable for snow if cautious”. I don’t know what the stock tires are on your vehicle, but recognize that OEM tires are selected generally for cheapness and compatibility across the vehicle line rather than for optimal performance, and so you may want to consider a different brand and make of all-season all-weather tires. I use a semi-premium (but not terribly expensive) brand of all-weather, all-season high performance radials on my car (also a Subaru) and haven’t had any problems driving through rain and light snow through mountains, although in those conditions I admittedly don’t try to drift around corners in an effort to replicate heart-pounding scenes from Frankenheimer’s Ronin. Tirerack.com provides some good, reasonably unbiased information and reviews on different brands of tires, including actual driving comparison. For the kind of conditions you describe, snow tires shouldn’t be necessary, and will create more noise and wear faster than all-season tires. Chains are unnecessary (and depending on your model, may not fit on your vehicle) unless you are driving on incline on hardpack snow, and will also tear the crap out of your tires if you use them frequently.

In summary, buy good quality all-season tires, slow down in snow and rain (if you think you might be going to fast, you are going way too fast), and don’t assume that the “AWD” badge and the marketing hype about Subaru Symmetrical All-Wheel Drive, Vehicle Dynamic Control, and “four channel, four sensor, computer-controlled, antilock brakes” is going to fundamentally change the laws of physics in the immediate vicinity of your vehicle.

Stranger

This is why I always chuckle to myself when people make comments that “No one around here knows how to drive in the snow!” because a certain number of them actually mean “people slow down way too much for my taste.” I tend to think those are the people who haven’t had their accident yet.

Also, if your Subie has a manual transmission now is a fabulous time to learn how downshifting slows your car without need of brakes. Low gears are your friend when stopping in the snow and slick, although for going forward you want to be in the highest gear possible without actually lugging or stalling, because that way you have less chance of sliding around as you apply gas. The best trick for driving in snow is to behave as though your pedals are made out of eggshells–you want to be very, very light on them at all times. Try stopping your car from 30mph while assuming your pedal is going to break off if you apply more than a few ounces of pressure and notice how long it takes for you to actually stop–that’s what braking in snow does.

Well, no, some people really are way too overcautious in the snow, or plain just don’t how to drive in the snow. Now keep in mind that upthread I said I slow down and drive cautiously, but there’s still a balance between obstructing traffic and endangering yourself and others.

Having spent most of my life in western Canada, I can confirm a few things. First, a Suburu with all season tires is significantly inferior in the snow to a random front-wheel drive with snow tires. I’ve driven both. Second, there just isn’t a lot of friction to be had on snow (though modern true winter tires are pretty freaking amazing), so you have to do things slowly and over a lot of space. This means braking lightly and way earlier than normal. This means leaving way more following distance than normal. This means slowing the fuck down. Third, there is no magic solution to the dangers of icy roads. Technology won’t save you. You have to do it yourself by recognizing how slippery things are and driving accordingly.

yeah, every winter I see some dimp with a BMW or something who is still running summer tires slide right through a stop, or sit there with the wheels spinning impotently.

several years ago I was that dimp (in a Neon though, not a BMW.) getting stuck in 1" of hard-packed snow on level ground is embarrassing.

I can’t state enough how much better real winter tires are in the snow. problem is that you’ll want to change them back quickly once the temps warm up or you’ll wear 'em out just like that.

you could get by with an M+S all-season, but they’re still not as good as a proper winter tire.

In areas that get frequent snow* some tire shops will store your winter/summer tires for you while the other is on the vehicle. I’ve toured my uncles’ tire shop in West Virginia, and they showed me a room filled with neatly stacked sets of snow tires, labeled with their owners’ names. (This was during the summer.)

Each fall and spring, these folks would come in and have the switch made. You might find this worth looking into…

    • I’ve never lived in one, personally, so it’s all-season tires year-round for me.

I have to agree. But, also have to consider that the only way to get snow driving experience is to drive in it a lot. I live in a ski resort area that gets folks from all over the world. You really have to give them special consideration both from a good host stand point, and a defensive driving stand point.

Thanks for all the responses. I was going way too fast for the conditions in both cases, probably around 20-25 mph. Also, I said all-season tires, but in truth I’ve never changed the tires. They’re just the original ones.

I have a dumb question about downshifting. I have an automatic, but it also features D3, D2, and D1 gears. Can I shift to D1 from D while the car is moving? Also, what’s the point of D3?

D’oh! That makes a lot of sense. I should have realized that not a lot of people have room to store four tires year-round.

I used to drive a Subaru Impreza, new enough to have all-wheel drive standard, old enough not to have anti-lock brakes. I had no real experience driving it in the snow as I tried not to drive in bad weather while in college and only took it out once during the Great Snow of 2006 in Albuquerque. So I had to really learn how to drive it when I moved to the Northeast in a December and the first week I was here we had a major ice storm. People have already pretty much said everything that can be said. Now, I did not put snow tires on the car and found that the only times I ever really had trouble was on stopping when I locked the brakes up once or twice when I should have just kept on going. The nice thing about the stick is that I could lay way off the brakes and just downshift.

Yes, you should be able to shift while driving. I believe the Subaru is a four-speed with overdrive. If that’s the case, it should be that D3 locks the car into no higher than 3rd, D2 into 2nd, and D1 into 1st. I would work the progression, though, and not put it straight into D1. The rev limiter should kick in but there’s no reason to put too much strain on the engine.

I know of an old Mazda that actually had a button on the shifter that would force the engine into 3rd for climbing hills and then has 2 and 1 in the pattern. The Impreza handled better with AWD and all-season Michelins than the Mazda did with FWD and only two snow tires. Make sure to get four snows, especially since in a Subaru unequal tire radii can wreck the differential.

I have a 06 subie with awd/abs. Going isnt a problem in the snow, stopping is. especially as mine has tires that trend more towards summer, but, thats also why i keep a set of chains. With chains on I can sled the car through much deeper snow (ymmv on damage, been lucky so far) and maintain control, and with the chains you can actually stop, just not by slamming the brakes on. Which chains on I was fine in snow around 19’’ deep as long as I didnt stop with the body supported by the snow.

Subaru note on chains: if you have a manual, chains on all 4 or else!
Automatic, read your manual, you either have subaru active awd, which means you can put chains on just the fronts( the rears still push, just at always varying amounts), or you have a fixed torque split diff, which I beleive again requires that you chain up all four wheels.

That’s probabably a big part of the problem. Some, Maybe mose OME tires are not that good.

Just leave it in D. In an automatic, don’t bother downshifting unless you are on a LONG steep hill - conditions where you think your brakes may overheat. This is a simple explanation of something that is a bit more complex. But from your OP, I would not worry about downshifting. Especially in the city with an automatic. Get to know the conditions, your car, and your brakes and tires. It does not seem that you would run in to brake overheat from the conditions that you described. There is NO need to throw another variable into your ability to stop in time. Your brakes will do the job just fine.

That’s a real nice service, never new it existed.

I too would be wary of how the transmission can unglue your connection to the road. Driving in a situation with poor traction requires smooth and judicious application of forces, whether it’s braking or acceleration.

When you manually shift gears, or when your automatic shifts for you, there can be a sudden change in the forces sent to the wheels. I once was driving very slowing down a sheet of ice and stepped on the clutch. This immediately resulted in uncontrolled spin - the little traction I had was gone.

Also - AWD systems are different than 4 wheel drive. I believe AWD usually means front and back standard differentials… you can have the situation where one back tire is stuck the other free with no traction - it will spin and the back is useless; if the front is in the same situation, you are stuck.

I have a very, very old Subaru (Loyale wagon) and it has very thin tires. Some friends have joked that “the 1980s called and they want their tires back”. Granted I’m semi- careful in snow, but the traction is a lot better in snow than cars I’ve driven with wider tires (an S-load better than my old heavy Explorer XLT, which wasn’t bad at all). I always chalked it up to total weight vs % of weight per inch of road contact… and maybe me keeping good rubber (lots of tread life) on her.

I don’t know if your model is designed to run with those tires, or of they only work on the old-fogey Subarus.
(…which were new when Clinton was first elected. Hey, its paid for. :frowning: )

Yep, well said. Particularly a problem with automatics going uphill in slick conditions. Once you know your car though, even in an auto you can anticipate this. Manuals are better overall for these conditions. Well, in pretty much all conditions, provided you can drive it properly.

This has really become a ‘black box’ of terminology. I consider my Pathfinder to be a 4x4. You must select 4 wheel drive if you want it. And, IMHO, to call something a 4x4 you must have the ability to select low range for off road. Yet, my Pathfinder does have ‘traction control’. I do have the ability to turn it off, which I do in deep snow. And it turns off automatically in low range.

YMMV of course, and there are different types of traction control. One thing that my traction control does is limit the overall power/speed/rpm output. This can be a very bad thing when you are trying to bash through some deep snow. Or turning onto a road in slick conditions where you need to accelerate and find that the engine won’t go much above idle for a second or two. A little tire slip is no problem, I may actually want to slide a little bit. I’ll take care of that myself thank you very much.

For general driving, I consider that the engineers that designed the car are much better than me to decide the tire width. So for my daily driver, I keep the tire size as specified. I choose the tire though.

Thin tires will often out perform a wider one on ice and snow. It is about the pressure on the road. It’s a tough balance to achieve. Especially considering the different driving conditions and quality of tire. That’s why I leave it up to the engineers.

Off roading is a whole different ball game of course. And snowplowing as well. The tires on my '76 Chevy plow truck are a bit wider and taller than stock, but they are also chained up on all four, always. A thousand pounds or so of snow in the bed gives me incredible traction. The only drawback to that and pretty much any 4 wheel drive is that when you are stuck, you are definitely stuck. Just hope the sun isn’t going down to soon.:smiley: