an opinion
article
by As winter settles in and the snow falls, I’ve noticed a number of amusing things regarding drivers and their misconceptions about the capabilities of an SUV. While driving home in my Jeep Wrangler on I-95 the other night, I watched as drivers [New York, New Jersey and Connecticut] slipped and slid through the ice in their expensive cars. I listened to my police scanner to the numerous accidents around me, so many accidents in fact that one particular transmission caught my ear.
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Highway Patrol: ‘I need the location for the next incident.’
Dispatch: ‘You don’t need a location, there are so many that you can just drive up and down the shoulders and you’ll find ‘em quickly.’
Anyway, I digress. My point is that many people assume that because their vehicle has AWD (all wheel drive) and some form of traction control, that the car will always have traction thereby meaning they can continue to drive normally. Wrong Wrong WRONG! To begin with, it is necessary to understand what options exist.
- Part Time 4WD
- Full Time 4WD
- AWD
- 2WD Rear
- 2WD Front
Starting with the worst, two wheel drive obviously limits the number of tires actually contributing to traction. It’s generally understood that front wheel drive handles better in slippery conditions than a rear wheel drive vehicle. AWD differs from 2WD only in that two additional tires are turning. The misconception is that all AWD means that four tires always turn. That is not how your car works.
The drive shaft from the engine connects to a differential which distributes power to the axles and in turn rotates the wheels. But what is a differential? Put simply, it is a collection of gears that allow the two axles to rotate at different speeds. This is necessary in order for a car to turn (as the outside tire must traverse a greater distance than the inside tire) without having the wheels skip. Obviously, wheel skip introduces a loss of traction and thereby control. While the differential serves this crucial purpose, it is also the differential that creates the "one wheel turns, the other doesn’t" problem. The differential gearing transfers the power into the path of least resistance, which is often the wheel that has no frictional contact with the ground.
Back to all wheel drive. So long as all four wheels have equal footing, it is true, all four tires will turn with an equal amount of power and traction. However, just as two wheels on an axle are connected by a differential, the front and rear drive shafts are connected by a differential as well. This means, if one wheel of an AWD vehicle loses traction, the problem is amplified because ALL of the power goes to that one wheel while the other three sit stationary. This is why, without a form of traction control, an AWD vehicle is useless in any condition other than dry pavement.
A full time 4WD vehicle is essentially just an AWD vehicle that has the ability to "lock" the center differential on command. What this means is that when the lock is engaged, the front and rear drive shafts can be thought of as a single, solid shaft. Hypothetically, if one front wheel were to lose traction, it would spin while the opposite front wheel remained stuck. However, because the rear drive shaft is locked, both rear wheels will turn which will free the vehicle and – ideally – move the car forward such that the spinning wheel regains traction. The center drive shaft should only be locked in conditions that warrant such behavior because it will have negative traction effects on dry pavement when the vehicle attempts to turn (for the reasons noted above about differentials).
A part time 4WD vehicle is essentially a 2WD vehicle for all normal conditions. When 4WD is engaged, the front and rear drive shafts are locked immediately. Part time 4WD vehicles do not have the option of having the transfer case operate as an open differential. The drive shafts are either engaged and locked together or only one shaft is engaged. Typically, part time 4WD vehicles also have additional low-gearing options giving them tremendous amounts of torque to free themselves or tackle difficult obstacles.
Up to this point, it is obvious how part time 4WD, full time 4WD and AWD each have their strengths and weaknesses given particular road conditions. Additional technologies contribute to increase the likelihood of having traction in the event of wheel spin. The most fundamental device is called the locker. The locker principle was alluded to in the discussion on full time 4WD for locking the center drive shaft. Lockers also have their place in the differential, preventing the axles from spinning separately by locking them together "like a spool." A variety of lockers exist that can engage automatically or manually on demand in order to guarantee that two wheels will always turn. This sort of option typically only exists for off-road 4×4s and trucks.
The next tool for preventing wheel spin is called the limited slip differential. These differ from the standard open differential in that a coupling device is incorporated to allow axles to spin at different speeds, as necessary for a differential to function, but not at vastly different speeds, which is indicative of traction loss. A limited slip differential can be coupled by viscous fluids or a series of clutches. Ultimately, however, the limited slip differential keeps the wheels with traction turning allowing a vehicle to continue moving. As an example, take a standard AWD vehicle. If the right rear wheel loses traction, it receives all the power while the remaining three wheels do not turn. In a Jeep Wrangler Unlimited, if the right rear wheel loses traction, the limited slip differential will transfer power to the left rear wheel and the locked transfer case will transfer power to both front wheels allowing the 4×4 to continue moving.
Lastly, AWD vehicles regain some of their usefulness in slippery situations with the addition of traction control. The most common implementation is called electronic traction control which, counter-intuitively, uses the brakes. This system will be employed on vehicles with anti-lock brakes because a computer already has sensors monitoring the wheel rotation. In the event that a wheel begins to spin beyond a normal threshold, the electronic traction control system will actually begin to activate the brakes on that specific wheel – independently pumping up to 100% braking power. This has the effect of stopping the errant wheel’s spin completely – which, utilizing the path of least resistance, will transfer power through the open differentials to the remaining wheels in contact with the pavement. The system works fine for mildly slippery conditions, however on ice it can be dangerous because the car itself is repeatedly applying full brake force on the sliding wheels which prevents them for regaining rolling traction during a skid. A mechanical alternative to electronic traction control exists in the form of the Torque Biasing Differential [pdf]. Through a series of worm gears, torque biasing creates a mechanical advantage to the high-traction side of the differential which helps to prevent wheel spin. These differentials are often found on the front axle of performance tuned road cars. Torque bias differentials are not suited to 4×4 applications because they do not handle having one wheel lifted from the ground completely. (Notably, the HMMWV uses a torque bias differential and compensates for the raised wheel by applying both throttle and brakes simultaneously like a manual EDL.)
In summary, contrary to what owners believe, an SUV with AWD and traction control really is nothing more than a mini-van with big tires when it comes to slippery surfaces like snow, ice and off-road conditions. As such, it is necessary to continue driving them in winter conditions with the same due diligence as any driver of a vanilla 2WD vehicle. While true 4×4s and off-road vehicles have a definite advantage in the snow and ice, they too must take due care as an out of control SUV will cause them just as much harm whether they’re firmly planted or not.
Similarly tagged OmniNerd content:
- Terrafugia Flying Car, by VnutZ about 1 month ago
- Troubleshooting a P0129 OBDII Code, by VnutZ almost 2 years ago
- Porsche Takes a Novel Approach to Electrics, by VnutZ about 2 years ago
- Science Shows Women Distract Men, by VnutZ over 2 years ago
This article was edited after publication by the author on 29 Nov 2010.
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Physics Lessons on the Median Strip by gnifyus :: NR6
Just a few random comments. First, this was a great summary and explanation of the options available in these vehicles. I imagine though, in the case of the AWD vehicles, most of them must have the traction control by now. We had a 2001 Dodge Caravan with AWD and quite frankly it was awesome driving in the snow. Once in awhile I would have to drive down roads with 4 to 5 inches on them during or after a storm, and other than the resistance felt from the actual snow, it was no problem at all. It tracked straight and did not slip enough to notice even when starting on steep hills. (Unless on pure ice, of course.) This from the description of how the AWD in it works:
Under normal driving conditions, the device sends up to 90 percent of the power to front wheels, so the minivan drives like a front-wheel-drive model. Yet when on-board sensors detect wheel slippage in front, the coupling immediately transfers some of the power — up to 100 percent, depending on the amount of slippage — to the rear wheels. By channeling power to all wheels, Grand Caravan AWD remains stable on wet or dry pavement.
But, it was still a minivan. You couldn’t go "four wheeling" with it; there just wasn’t the clearance or the power.
The thing is, as you mentioned, people seem to not only think they can drive "normally" during snow and ice conditions, (which was probably too fast to begin with), but they suddenly feel they are immune from the laws of physics just because there is a ‘SUV’ or ‘AWD’ designation on their vehicle. It doesn’t matter what you’re driving, if you hit a slippery spot going around a curve, the centrifugal force is going to do its thing and off the road you go. Stopping is the other thing. Just because you can go a little faster doesn’t mean you can necessarily stop any faster than that rear wheel drive car you left in the slush at the last set of lights, especially if your vehicle is heavier.
Winter driving is a learned skill I take for granted sometimes. The issue is fresh in my mind because I have a 16 year old son getting his license soon. The secret really boils down to: ‘’No sudden movements." Don’t take off fast. Don’t stop fast. Don’t go around a corner or curve fast, and leave yourself time to not have to be in a situation of stopping or cornering faster than the physics of the situation allows.
Last February we were driving back from Florida and hit a rare snowstorm in southern Virginia. I am always amazed at how many cars (most of them SUV"S of some sort) were backwards in the median strip or worse.
Jerry by Anonymous :: NR0
My experience has been that traction control has some problems on steep hills when you’re going slow and you have to "spin" up the hill – the engine practically shuts off.
I must confess that I really like most Subaru’s in the snow and on ice. The only problem is that they don’t have enough clearance for the big snowfalls in mountain areas and they certainly aren’t a good mud bog 4×4 farm truck. I’ve even seen people in lake-effect areas jack their subarus up to counter this.
However, to me the biggest danger to safety is being on black ice without knowing or driving sideways a bit when you’re on mixed traction and then hitting road. That’s where Subaru shines because they don’t torque steer nearly as much as most other brands, they are a lot smoother in mixed traction, and they are low to the ground which makes it easier to pull back straight in-line when your tires start to grip again.
don't forget... by Anonymous :: NR0
…there is a difference between mechanical locking fidderential and viscous differential. Most passenger vehicles, SUV’s and light trucks are viscous clutch plate type diff’s. Some Audi’s and Subaru’s have mechanical locking differentials. Subaru for instance, depending on model(STi, for example) has a electronic adjustable center diff and 1 each front and aft(3 total). Audi Quattro’s uses Torsen center differentials and some of the transverse mounted engine cars uses Haldex electronic locking diff’s(also found on some VW’s). When locked, it is a true 4WD.
Also maintenance of the diff’s makes a difference as the clutch plates do wear out. Since it is rather expensive to service the diff’s, most owner hardly ever have them service during the life span of ownership.
What about Auto 4WD by robertjw :: NR0
My sister has an 07 Chevrolet Tahoe with an Auto 4WD setting. I’m not sure exactly how this system functions, but I do know that GM SUVs have had a similar system in place for the last 10 years. I also know that it works remarkably well. I had an opportunity to drive her vehicle during a recent snowstorm and the performance of the system was amazing. I saw little need for the 4wd High setting on the vehicle for the average driver (the 4wd Low is still advantageous when the vehicle is stuck and you need to crawl out of a situation).
A couple other comments.
Remember that there is very rarely a situation where driving on ice results in ZERO traction. Even in the iciest situations there is some traction and a skilled driver can maintain some control over the car.
Second, one of the big differences in FWD and RWD cars is the amount of control after the vehicle loses stability. In a FWD car ALL of your steering, power and most of your braking are controlled by the front wheels. If the front wheels slip there is little hope in regaining control of the car. In a RWD car the power function is in the rear wheels. In many situations, even if the front wheels slip and you lose steering and braking you will still have an option of applying power and using the application of that power to maneuver the vehicle.
4x4 in Desert. by Anonymous :: NR0
I have a Mitsubishi Pajero 2005 4×4 with option of Manual 2WD (Rear), 4×4 Fulltime, 4×4 high & low including electronic traction control & ABS.
I drive this car in the Desert where the wheels are 6-10 inches deep in sand and it really require a lot of power to keep the car moving.. Infact I have felt that this car does the job extremly well in handling such situation. I put the Car in 4×4 High on low sand and 4×4 on deep sand conditions and it just work well..
Infact I have pulled out numrous cars stuck deep in sand spinning rear/front wheel of those people who beleives that their expensive sedan must have all the necessary equipment & Power to take them out of sand… !!!
I am not sure how it would work on snow/ice as we dont have it but it is quite stable during rain as well… I beleive the traction control & ABS keep it from spinning…
But nothing compared to Cautious driving in extreme condition, as mentioned "No Surprise/sudden moves..!!! is the key.
Good luck, drive safe and enjoy your rides.
This article is flawed by Anonymous :: NR0
Without a detailed examination of different differentials and how different cars employ them, stupid remarks like "This is why, without a form of traction control, an AWD vehicle is useless in any condition other than dry pavement." shows up just how little the author knows.
And anyone who knows anything about cars can tell you the drive train is only about 20% in the handling/traction equation. Tires (tyres) contribute 50% of the cars ability and suspension 25%. The remaining 5% comes from everything else.
Scandinavians Appear To Be Immune To This by Anonymous :: NR0
While the science appears sound, real-life suggests differently. While with the Marine Corps I spent time in Norway on numerous occasions. Lots of Volvos, Saabs, Audis, etc. with AWD. They routinely blew us off the road in our Humvees. While I wouldn’t want to take one of these vehicles off-road (nothing beats a true military Humvee off-road), on packed snow they made us look like kids in soapbox derby vehicles.
Ultimately it comes down to experience and driving ability. I’ve seen plenty of "real 4WD vehicles" in the ditch during light snow; usually because the driver felt invincible.
Learn to drive the vehicle you have properly. Learn your vehicle’s limitations. Learn your limitations. And remember: you can’t drive as well as you think you can. (Just ask your friends and family; they’ve been trying to tell you that for years.)
I love my Subaru by Anonymous :: NR0
Living in Salt Lake City we get a good amount of snow. Not nearly as much as where I’m from, Buffalo, NY.
I purchased a 2003 Subaru Outback this year and as long as you know how to drive in the snow a Subaru will get you almost anywhere you need to go safely. It uses a viscous Limited Slip Differential. I’m not an expert on all the types of drive variations but I can safely say I am more than elated with the way my Subaru performs in the snow.
I’ve driven past quite a few SUVs stuck spinning their wheels because they were rear wheel drive, so if you live in an area that gets snow regularly and want an SUV I recommend you make sure to get some form of 4 wheel drive and not a rear wheel drive vehicle. I ended up digging a neighbor in his BMW 545 out just yesterday. I’ve also had a rear wheel drive vehicle for a short while and it was simply not safe in the snow (putting weight in the back or not).
Audi AWD by Anonymous :: NR0
I have an Audi A4 Quattro AWD without traction control and I can tell you from lots of experience that this car is unbelievable in the snow. We just had a 3 week long series of storms in Vancouver, BC and I was literally plowing through foot deep snow. Many times I pulled over to help push people out of the snow and I would park the car in deeper snow than they were stuck in. I never got stuck once. I agree that if you had one tire on ice it would spin but in real life driving situations the car was amazing.
One piece of advice is to avoid wide tires on snow/ice and use winter tires, not all season, for max. traction.
AWD Mountaineer by Anonymous :: NR0
I have a 99 AWD V8 Mountaineer with ltd slip rear differential. My testing ground is a 1/4 mile uphill washed out gravel driveway in Northern VT where the slope varies between 8 & 16%. Try walking up a snow and ice covered 16% slope and you may well be doing it on your hands and knees! In the winter 4WD and snows are a must. The only time I couldn’t make it up was attributed to Michelins with 80,000 on them. Cooper Discoverer Snows will get me up smoothly everytime, without the mad dash and thrash that most owners of 4WD’s insist is necessary to make it. The author’s theory of AWD may be true for some vehicles but certainly not mine. I have never been in a situation, ice or not where one wheel spins leaving the other three immobile and god knows I have tried! Another benefit to AWD that 4WD cannot boast, is even tire and tread wear without the necessary/constant need to rotate the tires. Any 4WD I owned was a guarantee to scalloped, uneven tire wear resulting in a loud rough ride and never getting much more than 40K out of a set of tires. I have 194K on my Mountaineer on the original snows and only the 2nd set of summer tires, I got 100K out of those original Michelins! I’ll take AWD over 4wd anyday!
very misleading arcticle. by Anonymous :: NR0
Your statment “AWD vehicle is useless in any condition other than dry pavement.”
and is one the more ignorant statments I’ve read lately.
Buick Rendezvous AWD by Anonymous :: NR0
I had a Rendezvous with AWD and loved it. However, it was a 6-cyl and when the gas prices went up, I couldn’t bare filling the tank worth of $50 of gas once a week. I traded it in for a car that gets 35 mpg avg versus my Rendezvous that got 16 mpg avg. Unfortunately, last winter I found how much I missed the Rendezvous.
In comparison, I had a GMC Jimmy 4×4. It spun out often on wet roads, especially when I had to pull out into fast moving traffic on a local highway, which happened to be on an incline. I hated it and felt having to put it into 4WD when I think I needed it versus the Rendevous doing it for me when I didn’t know I needed it was awsome. I knew right away I made the right choice when I had to pull out onto the crazy highway in the rain and had no problem what so ever.
The last year I had my Rendezvous, we had a snow storm that dumped 2 ft of snow. People were stuck trying to dig their cars out. I jumped in my Rendezous, put it in gear, and off I went. Mind you, I don’t drive like I am invicible either, I take precautions, but I will never go back to the standard 4×4.
However, I am considering my next vehicle to have either Intelligent 4WD or a 4-cyl AWD. I found many of the 4-cyl AWD get way better gas mileage (23 mpg avg) versus the 6-cyl AWD. I don’t know much about the i4WD, which is why I came to read this article.
I am wondering if there are any issues between a 4-cyl versus a 6-cyl AWD other then power. Will the difference in power effect me when driving in snow? Also, is the i4WD the same as full-time 4WD? I have had people try and tell me i4WD is the same as AWD. If so, why don’t they just call it that. All I know is that I really liked the AWD, but I didn’t like the gas mileage.
AWD, 4WD = Invincible Thoughts = Time in Ditch by Anonymous :: NR0
People are driving way too fast for the road conditions, more-so if they have AWD or 4WD.
I have never heard of someone in an accident say “if only I could have gone faster…”, it is usually something like “I couldn’t stop quick enough”. We all still only have 4 wheels available to stop!!!
Slow down. Slow down even more when the roads are wet. Slow down even more when they are snow covered and/or it’s below freezing.
Put on good snow tires for wintertime driving. It makes a Big difference and the cost is just a little more (you are always only wearing out just 4 tires when driving – summers or winters).
All-season tires are Not the same as Winter tires – get the winter tires with the little mountain and snowflake icon on the side. Make sure you have good tread life left on the tires no matter what the season. On dry pavement tires with half tread life left still perform acceptably but on wet or snow covered roads their stopping performance drops Significantly!
I have only owned 2WD RWD vehicles in my lifetime (pickups, 4d sedans, and SUVs), never owned a 4WD or AWD or front wheel drive. I travel upstate NY all year around between Buffalo, Binghamton, Albany and Watertown. Never been stuck, never been in an accident. Therefore I know that it can be done.
Happy & Save driving everyone :)
AWD vs. FWD in an SUV by Anonymous :: NR0
I live in the Chicago area where we can receive anywhere from very little snow during the winter to over 60" in any given year. I am considering purchasing a new Volvo XC60 and while I understand the basics of having AWD, I like the gas mileage on the FWD even better! Any words of wisdom to help me make my decision?
Two Years Later - Same Thing by VnutZ :: NR10
Almost two years to the day from writing this up, the NE got slammed with a winter storm. We didn’t get nearly the same amount of snow that everyone else got but still got quite a bit of accumulation. Yesterday while driving up a steep hill there were lines of sedans (to includes some AWD models) struggling to go up the incline with spinning tires and sliding.
Now a good part of that is probably also that sedans are sporting all-season tires and not all-terrains. Those are atrocious in snow and ice. But people just assume their AWD and traction control will work for them in all conditions because it handles so much better than 2WD (it does) on flat ground. But on that steep hill, my Jeep in 4×4 just drove up and past them with turning maneuvers to get around everyone like it was dry pavement.
Subaru Outback ice traction by Anonymous :: NR0
The car handles nice on dry pavement but seems to have no traction on ice. It is as if the traction control is confused and at a total loss as to what to do. Ice around the freezing point is virtually frictionless. It is at that temperature and a few degrees below freezing when the car feels like it has no traction whatsoever. We used to have a front-wheel drive (FWD) vehicle with 80 series all season tires and it handled ice better than the the Outback with its lower profile 60 series tires. Less weight per square inch of tire contact is the last thing needed on ice and yet that is what low profile tires do. A friend who bought an Outback around the same time took a three day drive through a winter storm from Montana to Phoenix and had never been so terrified in their life due to the absence of traction. Whereas winter tires were an option on our former FWD vehicle, they appear to not be an option on our Subaru. If winter tires do not substantially correct the problem then the car will have to go for safety reasons which would be unfortunate because it is otherwise a premium vehicle.
Pass on the AWD... by Anonymous :: NR0
I had a 2002 AWD Subaru forester, it sucked it the winter. Even with brand new all terrain tires I would get stuck in a snow mound from the snow plows. The front tires would spin, trac. cont. would kick in and move all power to the rears thus giving me a RWD vehicle. Even with getting a running start it would never make it. My 4×4 pick-up never had a problem with snow, ice, mud or rain. Through thick and thin it has always come through. (pun intended)
The people that dont know how to drive in adverse weather conditions need to stay home and save other peoples’ time from pulling them out of the darn ditch. All it does is back up traffic. Learn how to drive, stay home, or MOVE SOUTH…..
A limitation of 4X4 on ice by Anonymous :: NR0
There is one limitation to 4X4 that you may have not realized.
When the center is locked on a tight turn the front tires have to go a longer distance than the rear tires, but are turning at the same average speed as the rear tires. This causes them to get pushed by the rear tires. Which is why you aren’t supposed to engage 4X4(part time) or lock (full time) when you are on dry pavement, something is likely to break. But in a situation where traction is minimal it could cause a skid to occur.
Btw, my CJ even in 4X4 is almost useless on ice, because the tires aren’t meant for ice.
AWD vehicle is useless in any condition other than dry pavement.?????? by Anonymous :: NR0
The statement “AWD vehicle is useless in any condition other than dry pavement.” is just absurd. My 2005 astro van AWD is incredible in the snow and sends power to the wheels that need it when they need it. I would not hesitate to take it out in ANY snowstorm.
My Experience by Anonymous :: NR0
I love cars and I have had over 12 4×4 or AWD vehichles. I currently own a Lexus AWD SUV with traction control and a Jeep Wrangler 4X4 with a suspension lift kit and 33 inch off road tires. Obviously as others have said things such as your speed, road conditions, tires, etc make a world of difference if you will be in the ditch or not. I dont know all the technical reasons behind things but I do know what my experience has been. I think that not only does traction control, transfer of power etc, matter but also what percentage of power is coming from the rear tires and the front tires. Obviously this might be accommodated for by systems which distribute and readjust power. But in older vehicles or less sophisticated ones, this might make a huge difference. My Lexus way out performs my Jeep in light snow (few inches) or ice. The Jeep which is an older model but in great shape, will still fishtail easily in 4WD if I am testing out its traction while the Lexus will not. But I would put my Jeep against the Lexus any day in much deeper snow, mud or crossing a river (lol). I think the Jeep is geared towards having more of the power distributed to the rear tires which is traditionally needed for more powerful thrust and would rather have more power in the rear wheels if I am in deeper mud or snow. But rear power has the ability to fishtail a vehicle while front power does not unless going around a curve. I believe the Lexus has more evenly distributed power or emphasis on front tires or greater ability to adjust power. So just be careful and know your vehicle. I’m even more careful with the jeep in light snow or ice but its grabs great in heavy snow.
Have you lost your mind? by Anonymous :: NR0
AWD useless except on drive pavement? That’s ridiculous.
I have an AWD Jaguar x-type with no traction control, a porsche carrera 4 with traction control a f-150 4×4 with warn manual hubs and manual transfer case and a 1972 CJ5.
Jag AWD system keeps power to ALL 4 wheels and a 40/60 power split front and rear. I run Blizzaks in the winter and Michelin Pilot Sport AS Plus in the summer and it’s the best driving winter and wet road car I’ve ever owned (including an Audi S4) and the Porsche C4 that runs Michelin Alpin Pa3’s. My Porsche also keeps power to ALL 4 wheels at all time but has a dominant 31/69 power split front and back. The truck and jeep are the worst in slick icy roads but best in deep snow, mud and off road.
I’ve driven all sorts of 2 wheel drive cars in the past with good or studded snow tires and I lived in Alaska and drove the Old Seward Highway from Girdwood to Anchorage EVERY day in gnarly winter conditions..including whiteouts.
Bottom line is that their are loads of AWD cars that keep power to all 4 wheels which, combined with proper tires provide significantly more traction than their 2wd counterparts.
Awd vs 4x4 by Anonymous :: NR0
Awd if far better in the snow than 4×4 and here’s why. I have seen 4×4 in the snow and every time up a hill only 1 front wheel and one opposite rear wheel works not all four and I have seen this many times on 4×4′s getting stuck. A truly good awd system can get all wheels moving and spinning. Part time shift in 4wd really sucks. It’s only for light snow or heavy mud. Put both on a 4 wheel dyno you’ll see the truth. Subaru is proof of this with their awd system.
AWD vs 4x4 in ice conditions by Anonymous :: NR0
So we all can agree about ice conditions, it sucks for all types of drivetrains> Now the driver may be able to drive through the situation with ease (traction control or not, lockers or not, chain tires or not) because of experience. If you put a kid in the best 4×4 or AWD vehicle setup they will still get stuck or run off in a ditch with an inch of power snow on the ground. But it goes back to the point of: learn how to drive, stay home, or MOVE SOUTH.
Has anyone mentioned the full-time 4×4 Hummers(H2 & H3)?
It all comes down the person behind the wheel... by Anonymous :: NR0
This has been a very interesting read. There are people who are very tied to 4WD and there are those very tied to AWD. To some degree, the argument will never end :). Having driven a my old 4WD 4-Runner and my brothers Outback through some Masschusetts winters, I can say both performed admirably. Both systems have their merits and drawbacks. Which one is better for you really comes down to your needs. In terms of how well any of them function, however, I think comes down to the ability of the driver. If you don’t know how to drive in inclement weather and/or on various surfaces, and you think AWD or 4WD is there to magically do all the work for you, then you’re an idiot. You can have the best tools in the world, but that won’t matter much if you don’t know how to use them.