FWD Can't Climb Hills In Snow?
Posted by Tape_Face42@reddit | askcarguys | View on Reddit | 141 comments
I'm struck by the conversation in this post from the the other day about someone struggling to climb a 10% grade with their FWD car, even with winter tires. I don't want hijack that post, but I'm confused by the replies. I keep reading people saying things like "FWD is great in snow". However in this post we have a bunch of people saying that FWD is bad at climbing snowy hills. Some saying "FWD just sucks uphill in the snow", many saying "Reverse up the hill".
I would think that the ability to climb a snowy grade would be maybe the most important element for a car to do well in the snow. Yet here people are saying the opposite. I of course find that contradictory and I don't understand. Is FWD better in the snow or not?
DJScaryTerry@reddit
People forget the most important part that's why.
A good differential can make all the difference.
Iffy50@reddit
I don't understand the logic here. A differential allows the two tires on the same axle to turn at different speeds when you are turning. How is that going to affect the ability to go up a hill?
nrubenstein@reddit
In this case "good" means "quality limited slip." Open diffs have a HUGE impact on hill climbing ability for any drive type.
Iffy50@reddit
Ah, got it. I call that traction control. Subaru has a great power management system for snow.
netopiax@reddit
Traction control works by braking the spinning wheel and/or limiting throttle - kind of a software layer added to ABS. Main point being, TCS is software and a limited-slip differential is hardware. AWD systems may have additional electronically controlled diffs.
Iffy50@reddit
Got it. The AWD vehicles I've driven had the ability to lock the differentials.
nrubenstein@reddit
I'm not aware of any AWD vehicle that has diff lockers. I'm sure it exists, but it's definitely not a Subaru.
Iffy50@reddit
My mistake. It was an Audi Quattro that had it. I thought my Subaru had one, but it did not. I never needed it though, it climbed hills very well with software.
nrubenstein@reddit
(Don't confuse limited slip with a diff locker, they are not the same thing.)
FordF150ChicagoFan@reddit
Differential and tires are everything! I had snow tires for my Camaro back in the day and also put 4 45lb plates in my trunk for extra weight over the axle and never had much problem. If given a choice I'd take RWD with a locking differential over 4x4 with open differentials.
AlwaysBagHolding@reddit
Every fwd car should come from the factory with a quaife.
Snobben90@reddit
I had a Mazda 626 from 1986. It was front wheel drive, and me sitting in it would account for around 10% of its weight.
No other car in my school was better at driving in the snow. I once even towed a guy who drove an Audi quattro.
Which wheels that are powered of course affect the cars ability to move. But the skills of a driver has the largest burden. Once when I got stuck I managed to get free by a simple gearbox trick for example, while a guy was about to push me but stopped when he saw me start to move by myself again.
tads73@reddit
If you ever driven a 2wd rear wheeled vehicle, you would realize how much an improvement fwd is. Its all physics.
Peter_Piper74@reddit
Native New Englander here and if you know how to drive in snow you can get around in almost anything.
Rear wheel drive? Get good snow tires a d put some sandbags in your trunk. Stay light on the gas.
FWD with good all season tires is all you need.
MentalAd2843@reddit
A 10% grade is quite a lot. If you don't have snow tires or chains which can grip the snow, once it starts to pack and the sipes fill with snow you're going to have a difficult time. That's whether it's a FWD or RWD.
The reason people say FWD is better is because you have the weight of the engine on the front so it tends to give you better traction, but it's not a cure-all.
Ponklemoose@reddit
Even that (IMHO) is a mostly attributable to the giant turds that the early FWD cars replaced and a little marketing. Modern RWD cars tend to have pretty even weight distribution and splitting steering and propulsion between different tires has value.
Ok-Armadillo-392@reddit
The only rwd cars left are for the most part sports cars or luxury cars.
FordF150ChicagoFan@reddit
Also full size trucks and SUVs are RWD with part time 4x4
Ponklemoose@reddit
Correct. I'm saying that FWD shit boxes were better in the snow than RWD shit boxes, but the RWD shit boxes are mostly rusting in peace and took the big advantage of FWD with them.
All else being equal (I acknowledge that they never are), I'd probably choose a modern RWD car over an otherwise identical modern FWD car for snow and everything else except for fuel efficiency and interior volume.
HotmailsInYourArea@reddit
Yeah rear-drive BMWs actually do decently due to the 50/50 weight split
FordF150ChicagoFan@reddit
Also FWD tends to understeer in low traction whereas RWD oversteers.
bloodfeier@reddit
Came to say this…I live in a valley between 2 mountain ranges, and one of those had one of the steepest freeway grades in the state, it’s only a 6% grade…10% must feel super steep by comparison.
TheBigMan1990@reddit
You want it to load up with snow-that’s one of the reasons for all the snipes on snow/winter tires, snow grips snow.
Max_Downforce@reddit
The sipes are supposed to fill with snow. Snow on snow improves traction.
kondorb@reddit
Well, it’s definitely the worst of three options when it comes to climbing a slippery hill. Because weight transfers to the back even more than usual and you’re left with no traction. But the binary question can/can’t depends on many factors.
How good are your tires in snow?
How loaded your car is?
How steep is the hill?
How slippery is the surface actually?
Get good winter tires optimized for your type of winters and you’ll be OK 99 times out of a 100. Carry a good set of chains in your trunk for that 1 time.
Odd_Hat6001@reddit
You are only as good as your snow tires.
d0ugfirtree@reddit
Michelin X ice from the original post are excellent snow tires and he's still struggling for traction going up his hill, soooo I'm not really sure what point you are trying to make here.
Odd_Hat6001@reddit
Ok. If you can't get up the incline with snow tires would it be better with all season? I doubt it. You don't know what you don't know. Freezing rain, nobody is going up. Winter tire rubber is better in the cold, there are snow tires for deep snow and others for slysh and rain. There are too many variables here. But there is no situation where all seson are better. At least not in Canada.
d0ugfirtree@reddit
But these threads are about drivetrains not tires, the guy already has Michelin winter tires on
Iceyn1pples@reddit
Just because they are using proper winter tires, doesn't mean those tires aren't a few years old, or have been driven too long on hot days. Lots of people get the winters on too early, and take them off too late, and thats mostly due to appointment availability of their local tire shops.
Those proper winter tires may no longer be in optimal condition.
Tape_Face42@reddit (OP)
Come on, can't stay on topic in reddit, that'd be silly.
exenos94@reddit
X-ice are shit snow tires. They're excellent ice tires. They're amazing for freezing rain, hard packed snow and the slippery stuff but I've had zero luck with them when it comes to actual deep snow. Theres not enough tread spacing for heavy snow and I find they just get packed up.
colaroid@reddit
I second this. I've had Hakkepelitas, nordmans, and winterforces that all were WAY better than the X-Ice in snow. All on FWD vehicles, except one set of winterforces were on a 91 MR2. That was fun. Hakkepelitas were my favorite, followed by the winterforce.
Busterlimes@reddit
100%
I used to blast past 4x4 trucks up the steepest hill in town in my MK4 jetta with snow tires.
exenos94@reddit
Mk4s are the only cars I've owned and I still can't get over how capable they are. Obviously my truck takes the win once the snow starts coming over the hood of the car but until then I'll take the golf out over my truck if it's bad weather.
fallguy25@reddit
My 83 Subaru 4x4 wagon was unstoppable.
ktbroderick@reddit
But what if you got stuck behind one of them and had to stop halfway up?
I drove a Mk2 Golf in Vermont for a few years and worked at Bolton Valley at the time; I never failed to make it to work with snow tires on, but I absolutely needed a running start to get up the S-turn on the access road a handful of times.
ExpensiveOccasion542@reddit
Fuck snow tires. I don't use them and I have a FWD car. I even drove RWD cars in the snow when I worked at a dealership. You are only as good as your skill level.
Odd_Hat6001@reddit
Does your big dick get in the way of the steering wheel.
mar78217@reddit
No, we use that to pry us out of a snow bank. /s
ExpensiveOccasion542@reddit
Do I sense a lack of skill?
Fun_Variation_7077@reddit
Yes. Yes you do.
KeeganY_SR-UVB76@reddit
Skill can’t beat physics. You must not know what it’s like to live in a place with lots of snow.
Fun_Variation_7077@reddit
What does that have to do with anything?
Kootsiak@reddit
You mustn't live with a lot of snow and ice because that statement would get you laughed out of my area.
I spent nearly 15 years of driving in northern Canada without being able to afford proper winter tires on my cars and trucks and i can say with utmost confidence that there is no substitute for good winter tires.
I would argue that winter tires make more of a difference for traction than any other dedicated tire for their terrain/conditions vs. an all season. The only exception being a proper track tire, like a sport cup 2 vs. some generic all seasons. That might be more of a difference but also a very abnormal application that billions of drivers will never experience.
ExpensiveOccasion542@reddit
I do. I live in the Midwest and have to deal with the lake effect snow.
gravelpi@reddit
You don't really test tires until you're doing serious hills. I grew up in the kinda-midwest too, Buffalo. We all drove on all-seasons and it was adequate. I live somewhere hilly now (with 10% grades and the like), and snow tires make all the difference.
bioweaponblue@reddit
Yeah this is the missing comment. A skilled driver can absolutely fishtail around an icerink traffic cone course and do fine.
The same is NOT true for steep hills.
Kootsiak@reddit
Lake effect snow can get pretty bad, but that's just normal snow where I am from. I basically live in the exact same latitude and climate as Alaska, if that helps you relate at all. So 5 months of the year most of the roads are hard packed snow and ice, where winter tires make ALL the difference and you'd have to be stupid not to feel it.
sharkdingo@reddit
Live on backroads and fishtail forward up that hill.
Always worked for me at least.
Any_Honeydew9812@reddit
and your skillset
Viper-Reflex@reddit
And your drivetrain
I had a 96 Riviera supercharged which has a limited slip differential that was pretty good.
Thing didn't care at all about 6 inches of snow in all weather tires.
mar78217@reddit
This too. My ex wife did not understand that to get up a hill you go easy. She had a jeep and would smash the gas and spin.
Technical-Math-4777@reddit
Or how many times you’re willing to bounce the wheel back and forth while trying to keep your automatic in low gear. Source: I used to own an Elantra.
mar78217@reddit
And your driving ability... I wound up sliding to the bottom of a hill in a minivan a decade or so ago in Chatanooga. I got back up the hill by moving the front tires back and forth like those toys we had back in the day that went forward when you moved the front wheels back and forth.
iHaveLotsofCats94@reddit
And your differential. A car with an LSD will perform better in low grip situations than one with an open diff. My Civic Si with Blizzaks was unstoppable in the snow
Fun_Variation_7077@reddit
I've always run all season tires. Never once did I have an issue.
Swamp_Donkey_7@reddit
I mean snow tires are great but they can't overcome physics. Put a FWD car on a steep grade, nose up and you shift the weight of the engine back slightly. Yes weight on the front wheels and more weight shifted to the rear.
In the same situation, in a RWD vehicle on a steep grade nose up, more weight would shift to the rear wheels so you might get a little more grip in that scenario.
The above is very simplified, and so many more factors would go into this, but weight transfer does affect traction immensely. It's why RWD drag cars can usually out launch a FWD drag car, and why front brakes on vehicles are more powerful than the rears.
OnlyCommentWhenTipsy@reddit
The most important element for a car to do in snow is STOP, and people always forget that all cars have 4x4 stopping. You're more likely to get rear ended by a suv with bald tires than a yaris with snow tires.
As for FWD vs RWD, it depends on weight distribution. RWD pickups are garbo in the snow until you're carrying something.
LWschool@reddit
Braking in snow is vastly more important, as well as cornering.
FWD is SAFER in poor traction conditions, not necessarily ‘better’. You get more control with RWD but it’s more risky.
Oversteer vs understeer.
Tape_Face42@reddit (OP)
Drive type doesn't effect braking.
TrineoDeMuerto@reddit
It sure can!
Tape_Face42@reddit (OP)
Not in this context.
Chris_PDX@reddit
It absolutely does, because the brake bias is different. FWD cars tend to have more front brake bias due to the extra weight up front (no sense sending more bias rear when the rear ends up being lighter than a comparable RWD car under braking due to the weight transfer).
Tape_Face42@reddit (OP)
You think a front engine RWD car isn't nose heavy?
mar78217@reddit
No, we've already discussed this. 3very rear wheel drive car (trucks excluded) still made are designed with a near 50/50 weight distribution. They are not nose heavy cars.
Chris_PDX@reddit
They are, but not as much as a FWD car.
The BMW 2 series is a good example, as it comes in both RWD and FWD variants in some markets. The RWD platform is roughly 50:50 (but still front heavy), and the FWD is roughly 58:42. Transaxle adds more weight, as does the mountain position of the engine.
Tape_Face42@reddit (OP)
Weight distribution =/= drive type.
RunninOnMT@reddit
Drive type GENERALLY correlates to engine mounting orientation though, which dictates transmission placement and transmissions are heavy. Also turning the engine sideways in and of itself self usually means more weight up front.
Tape_Face42@reddit (OP)
Lots of vehicles are longitudinal and FWD, not the point. Lot's of RWD vehicles are nose heavy as well.
The claim is that a FWD brakes better than a RWD, that is just not true.
RunninOnMT@reddit
Not lots, a few. The fact is FWD cars IN GENERAL are more nose heavy. That affects brake biases.
We are generalizing here, but we aren’t generalizing unfairly.
Tape_Face42@reddit (OP)
To be more accurate it effects weight biases, which effects brake biases. But it's the weight bias, not the brake bias that makes front heavy cars more stable under braking.
LWschool@reddit
Why are you arguing? You’re asking a question and we’re answering it.
Tape_Face42@reddit (OP)
Because it makes no sense.
Fun_Variation_7077@reddit
Yes it absolutely does. Have you ridden passenger with other people driving in the snow? Tons of people can't brake for shit in the snow.
Tape_Face42@reddit (OP)
Why?
nobikflop@reddit
Probably something to do with not understanding the threshold. They’ve driven their car tons on pavement and know when the brakes will lock up in those conditions, but they don’t have that experience in snow
Binford6100User@reddit
Think of the distribution of power when accelerating in AWD. Power, or more appropriately torque, is moved around through the driveline. It can be sent to wheels with better traction, overall resulting in the ability to apply more torque to the surface.
Now...... keeping in mind that the same connection between wheels exists.......understand that braking is just a NEGATIVE torque on the drivetrain. So if you can apply more power in AWD, you can apply more negative power as well.
NOW, the effects are diminishing at best because of weight transfer, driveline dynamics, front tire total grip, and a whole slew of other variables, so the practical application of this concept is small in real world usage.
Fun_Variation_7077@reddit
I honestly don't know.
LWschool@reddit
You asked a question and we answered it. If you don’t believe us, google it. Normal stuff.
SailingSpark@reddit
Learning to left foot brake can alleviate a lot of those issues with FWD. Right foot on the gas and left foot braking just enough to unlock the fronts will bring the slide under control. Just be careful you do not lock the rears.
Bi-mwm-47@reddit
It basically comes down to static friction. Maximum static force = coefficient of friction x Normal force (i.e. weight of the car)
Counter-intuitively, given the tires are constantly rotating, controlling a car’s motion is predicated on always having the tires in static friction with the road surface. Breaking free of static friction into kinetic friction is colloquially called “skidding“ or perhaps “doing a burnout.”
The coefficient of friction between snow or ice and the car’s tires is much lower than that of pavement and the car’s tires. At the same time, when a vehicle is being driven up a hill, it’s weight naturally shifts onto its rear wheels.
Demented-Alpaca@reddit
I mean 10% is a fucking steep hill. I wouldn't be shocked if a LOT of cars can't make that in the snow.
The steepest grade allowed on the interstates is 7% although I'm pretty sure there are a few sections in Oregon that, if you measured, might be rounded down to the nearest whole number.
xspook_reddit@reddit
"Back in the day" I had a FWD Ford escort with studded snow tires. That thing could damn near climb Mt. Everest. It was more capable than a 4WD truck with all weather tires.
AlphaDisconnect@reddit
Bad tires. Cheap tires. Worn tires. Summer racing tires.
Keep a small bag of sand, kitty litter. Pour in front of tires. Not a solution if there are other things wrong long term. But you should be able to crawl up.
Freezing rain is a heck of a drug. You will be driving normal. Then oops everything goes sideways, and now you slide backwards into a ditch. Or slide down a hill and need to call "Jesus take the wheel" and this was on good tires.
FutureHendrixBetter@reddit
As someone who has both a fwd and a rwd car you’re better off with fwd in the snow
Briggs281707@reddit
I've never experienced good traction on any FWD car. My GM fullsize cars have been real good in snow
yyytobyyy@reddit
It's also about technique and feel. Once I climbed a 40% inclined on an unpaved dusty road in an FWD car other people could not climb.
Most people just press the gas and send it. The magic is in knowing that you actually need a less gas, do it calmly, and feel what the tires are doing and adjust. If you don't have electronic differential lock, it helps to press the break a bit together with the gas.
Iffy50@reddit
I live in Duluth, Minnesota and I lived on a hill for 21 years. I had 2 front wheel drive cars for 14 years of that. The big advantage of FWD over RWD is the fact that FWD is more stable. FWD has more weight on the wheels because the engine is over the wheels, but that advantage suffers a bit on a hill. I still think FWD is better going up a hill. I always had All-Season tires, but only because I didn't want to have to swap them and store them every year. Winter tires are much better according to everyone I've talked to and every test I've ever seen. The type of snow makes an enormous difference, as does what is under the snow. The idea of reversing up the hill is interesting, but on most hills, it's better to get as much of a run as possible and try and maintain momentum as much as possible without spinning the wheels.
Ok-Armadillo-392@reddit
Idk if I actually believe op in that original post. They act like they are driving on a death road with cars piled by the wayside.
FemboyZoriox@reddit
Dude i couldnt make it up an icy 10% grade in an audi s5 with quattro with winter tires a few years back. Good luck lmao
Usernamerequired_92@reddit
They are right. On a hill the weight shifts to the rear so you have less traction. Here is a video demonstrating it. https://youtube.com/shorts/1XI_D6a5nNY?si=zNHYJvqWIDlVYzpW
pgc22bc@reddit
Swedish professional rally driver, Bjorn Waldegård said he would have preferred the Porsche 911 (rear engine) over the Porsche 914/6 (mid-engine) he drove for the 1970 Monte Carlo winter rally when it snowed. The Monte has a great deal of hill climbing over mountain passes. Waldegård lost to an Alpine A110 (rear engine). Having the engine hanging behind the rear axle worked great for them. On the other hand, Paddy Hopkirk, in 1964, won the snowy Monte in a front drive Austin Mini Cooper S. All this to say it depends... (On the driver, the conditions, the car and the equipment)
FIA World Rally cars have been AWD now for a very long time...since the Audi Quattro was introduced in 1980, nothing else could compete. This is the right answer for winter driving!
Tape_Face42@reddit (OP)
Funny, I'd just edited my post to add that vid.
ramman403@reddit
Canadian here, the ability to drive in the snow has more to do with the driver than the vehicle. A good driver knows to have winter tires on before the snow falls. When winter hits and you’re still driving on all seasons or worse summer tires, it’s hardly the cars fault. That being said, front wheel drive cars do perform better than rear wheel drive cars in the snow. Even a lifted 4x4 with studded tires can get stuck if it’s being driven by a moron.
TheBigMan1990@reddit
People say that FWD is good in snow because all of the weight of the engine is over the drive wheels-but modern cars are actually pretty balanced front-rear, so it doesn’t take much of an increase in grade to shift more weight onto the rear wheels than the front wheels. Tires and ground clearance will also radically impact the vehicles ability to climb a hill in snow though.
Enigma_xplorer@reddit
It's easy to understand if you think of it. When you are on an incline does the weight transfer onto the front or rear wheels? To make matters worse you are fighting gravity by trying to climb up a hill while the weight is being transferred off your drive wheels. Just imagine trying to crawl up a steep roof. Most of the weight transfers to your feet. Your feet slip your hand aren't going to stop the slide, they just don't have the traction.
pessimistoptimist@reddit
FWD are great until you have to deal with poor weight balance. Old Deawoo (bacame the Aveo) i had was a good little car until i had to drive up wet or slightly slippery inclines if i had a passenger. the com ined weivht of me and the oassenger shifted the weight balance enough that when i was on an incline the front wheels had less traction than normal. Just me i.the car and all was fine...but an extra 150lbs in the back seat made a big difference in that small car.
It is a given that you need the right tires for the conditions. Assuming you have the best tires possible FWD is typically easier to drive in adverse conditions when compared to RWD. do you need FWD? No, you can get by with RWD just fine, it just takes a different level of skill. Is FWD better in all situations? No, but in most typical scenarios it is. Everything else being equal, AWD can do things and go places that FWD and RWD typically cant and i would say is easier to drive 4x4 in your typical driving scenarios. Again, is it right for every situatio ? no, but it is a solid choice for most scenarios.
justdaisukeyo@reddit
My wife used to own a 1991 Acura Integra. She was paranoid about driving in the snow so she bought 2 studded tires (for the front only).
We live in an area where the snow melts in the day and freezes at night. It also snows only 2-3 times a year so most people do not have snow tires.
I was able to drive that thing up and down icy roads even with a decent gradient. I remember one time I had to zig zag upwards around cars and trucks stuck along a hilly road in order to get home.
After this car, we have had Subarus and other SUVs with AWD.
IMO, studded tires on a FWD car was superior than a Subaru with all season tires.
Blue8Evan@reddit
FWD is better on flat ground because RWD is prone to fishtailing, but uphill RWD is better since the weight shifts backwards and puts more grip on the rear wheels, putting less grip on the front wheels in the process, which is bad for FWD. It has less to do with the snow itself and more to do with the amount of grip you have and the fact you're moving uphill.
buildyourown@reddit
A 10% grade is very steep.
Tape_Face42@reddit (OP)
For an interstate, not for anything else.
Grandemestizo@reddit
FWD cars have the advantage of not being as prone to oversteer because there’s no power to the rear, so the rear wheels are less likely to lose traction. This in addition to the weight of the engine directly over the drive wheels makes them generally better in snow than a RWD car.
When climbing a hill, the weight of the car is mostly transferred to the rear wheels so a FWD car will struggle to put power down. It’s the same phenomenon that causes FWD cars to be bad at launching off the line. Once weight transfers to the rear they have all the speed and grace of a three legged dog on ice.
A RWD car will be able to put power down better on a snowy hill, but otherwise they’ll be more likely to lose traction than a FWD car in snow.
AWD is the correct drivetrain for snow. In fact AWD is just generally superior to FWD or AWD in virtually every performance metric with the downside being weight/complexity.
J-Rag-@reddit
If you're driving on a 10% grade in the snow you'll have more variable than just FWD vs AWD or whatever. How cold is it? Wet snow or dry snow? Snow pack? Fresh snowfall or leftover snow pack from a the previous day? Throw your chains on and you'll be fine in FWD though
pantherclipper@reddit
FWD is better than RWD in snow. However, AWD is much better than either.
Also, in the extreme edge case that you're climbing a steep hill in a FWD car while it's snowed out, then sure, a RWD would technically be marginally better. It'd be worse just about everywhere else, though.
ExpensiveOccasion542@reddit
Don't forget 4X4
pantherclipper@reddit
Yep, proper 4x4s (with the locked center differential) are the best in snow. Especially when stopping. A common issue people run into in snow is locking up the front wheels when braking. A 4x4 means you get equal brakes on all four corners since the front and rear axles are locked.
Fun_Variation_7077@reddit
I honestly don't understand locking differentials in the snow. How is it that moving both wheels at equal speed lead to better traction? I would think it wouldn't work as well, since power distribution when steering is inaccurate.
pantherclipper@reddit
Most 4x4s use a locking transfer case. This means a locking center diff, but still open front/rear diffs.
A standard AWD car with open diffs front, rear, and center will effectively lose all torque the moment any wheel starts to spin. That's bad because your engine power becomes unpredictable, since it gets turned to zero at random.
4x4s isolate the front and rear axles, which means to lose all torque, you'd need to simultaneously spin both a front and a rear wheel, which is much more difficult to do. This gives you a lot more traction to use.
Also, it means you're much less likely to lock up your brakes. Usually, the front brakes on a car are considerably stronger than the rears, since on asphalt the fronts do more braking. In snow, that usually means the front brakes immediately lock up, leaving the rears to do all the braking by themselves. Locking transfer cases keep both axles in check.
CapoKakadan@reddit
A typical AWD car these days does NOT have a center differential. It will have a clutch that can close completely if it wants to. It’s not gonna be like the two open diffs on the front and back.
SailingSpark@reddit
TL:DR 4×4 with a locked transfer case means two wheels will always have power. Two is greater than 1.
pantherclipper@reddit
Close:
Normal AWD means the moment one wheel spins, you lose power.
4x4 means 2 wheels can spin without losing engine power.
Fun_Variation_7077@reddit
Yeah but that would only apply to open diffs, right? Surely limited slip diffs don't suffer that.
pantherclipper@reddit
Limited slip diffs are a big upgrade over open diffs, yes. But nothing beats a proper locking differential off road.
A limited slip diff heats up as it slips. And technically, you still lose some power when losing traction with an LSD, as opposed to a locked diff.
Fun_Variation_7077@reddit
I'm not going to claim I know anything about 4x4 needs off road, because I don't. But when on pavement in the snow, how is it that a lack of side to side adjustment doesn't cause imprecise traction? Using 4x4 on pavement causes binding, so I don't understand how that changes on snowy pavement.
SailingSpark@reddit
Most 4x4s have open diffs. So it's not going to totally bind on loose surfaces if only the transfer case is locked. Power can still shift from side to side, just not forward and back.
Fun_Variation_7077@reddit
But if power can shift side to side, what causes binding on dry pavement? I swear I'm not being dense, I genuinely just don't understand.
Fun_Variation_7077@reddit
Yes but if the wheels receive equal power, how does that not break traction when the outside wheel is moving faster than the inside wheel? Using 4x4 causes binding on dry pavement, so surely 4x4 in snow means imprecise traction, no?
Fun_Variation_7077@reddit
Oh okay. So basically, you get the side to side variation, but 50/50 front to rear? If that's the case though, why does 4x4 bind on dry pavement?
pantherclipper@reddit
When you’re turning, the front axle draws a bigger circle than the rear axle, so the center differential still needs to exist to allow that to happen.
This is why 4x4s are usually only RWD in normal driving. You have to turn on 4x4 mode when going off road or in snow. My old Lexus LX was AWD + 4x4 though, that was cool.
Fun_Variation_7077@reddit
So if I'm not mistaken, only the center differential is locked, but the front and rear are still open or limited slip? If so, why does that cause binding on dry pavement?
pantherclipper@reddit
Because the front axle spins at a different speed from the rear axle when you turn.
Fun_Variation_7077@reddit
Yes but I'm talking side-to-side power distribution. When 4x4 is disengages, the differential sends different amounts of power between the two wheels depending on whether you are turning and how much you are turning. So how does locking them 5/50 side-to-side not cause traction issues?
pantherclipper@reddit
Locking them 50/50 side to side does cause traction issues on roads, and much worse than a center diff does.
But the benefits off road are huge. With fully locked diffs (front/back and left/right), you never lose traction when a wheel starts to spin.
Fun_Variation_7077@reddit
Okay I can kind of see that. But I still don't understand how that properly applies to snowy pavement? Is it just that there is always at least one wheel that somewhat has traction?
Tape_Face42@reddit (OP)
A hill is an "extreme edge case"?
Fun_Variation_7077@reddit
A lot of people simply don't understand how to drive in the snow. They don't understand how to feather the throttle, so naturally they lose traction. They also don't understand how to feel out a skid and correct it. I spent two winters in an old Civic with all season tires in New Hampshire, and never ran into issues.
Cicero912@reddit
Yeah I spent multiple winters in the Adirondacks with a FWD Ford Edge on all seasons.
Never had an issue
InformedTriangle@reddit
As someone whose been driving in norther Canada for 30 years, fwd all the way. That second video you posted also doesn't mean Jack because they cleared that course out so well it looks like a perfectly pristine, dry road compared to what the road conditions usually are up here... That test would have gone significantly differently if he was testing on two inches of black ice with 4 inches of snow on top of it in a blizzard for example...
HystericalSail@reddit
There's more to it than what's been mentioned. RWD with limited slip is going to be better than FWD with an open axle when it comes to traction, for example. Control has more to do with size and type of tires - long, skinny contact patch is better than wide, fat contact patch on ice.
I have a limited slip differential in my Jeep and I never feel the need to put it into 4x4 in town. The only time I've had to do that was when a snowplow built a 3 foot tall mound of ice in front of my driveway after a particularly bad storm in Colorado. In South Dakota the storms are milder, and though I live on top of a mountain I never bother.
My kid used 4x4 because he was 16 and it was his first winter driving, but not since then.
Ok-Ad8998@reddit
FWD is better in snow because it helps traction when more weight is over the drive wheels. But good tires and some experience with snow by the driver are as important for good winter driving as which wheels are powered. And, of course, AWD/4WD is better than two-wheel power.
SailingSpark@reddit
Its not just the weight, if you are turning and applying throttle, the front wheels can pull the car in the direction you want to turn.
Herbisretired@reddit
Until they spin, and then you go in the direction of the momentum which is why I usually let off the throttle a little when I turn.
cronx42@reddit
Snow tires are the most important then drivetrain. Awd will climb hills the best. Unless it has bad tires. It won't necessarily turn or stop any better with equal tires though. Awd is probably the best choice for most people in the snow, but fwd can also be very good and it's much harder to get stuck in a fwd. If you can't go any further, just put it in reverse and it'll come right out. Rwd will not.
Any_Honeydew9812@reddit
i live at the bottom of a hill and climb it every day in the winter. no problem, you just need to practice. i've done it with both summer and winter tires lol.
Living_Implement_169@reddit
Is it actually snow or is it ice packed? Even AWD can’t fuck with icy conditions
HeliumAlloy@reddit
The biggest problem with FWD is that it combines braking, steering, and accelerating into the same wheels.
I'd still choose FWD with new tires over an AWD car on worn-out tires. Snow-rated is better but all-seasons work fine, as long as they're in good condition.
Personal preference is RWD with good tires... but if you're asking the question then you don't want RWD.
Kootsiak@reddit
Ive driven all of them in northern canada and FWD is generally better for getting around than RWD in hard packed snow and ice.
Especially if you go down a residential side street or a driveway with a slight incline at the end, if you have to stop at the top to check or wait for traffic, you've got a much better chance with those front wheels at the top of the incline than rear tires pushing up against the car from below.
Just as an example, not that it's the most important part of what makes a fwd better but an example i've had in my life where it does make a difference.
9BALL22@reddit
On level-ish surfaces FWD has an advantage because the heavy components are over the drive/steer wheels, providing more traction and control. The weight transfer that occurs going uphill puts more weight over the rear wheels, reducing traction in the front. The steeper the hill, the stronger the effect.
newpsyaccount32@reddit
better than what? RWD? yes. awd? no.
bring in proper winter tires and it gets more complicated.. but also, the car itself matters. my fwd golf was unstoppable with chains on, i have a feeling my grandma's old Buick century might have felt quite different in the same circumstances.
i took that fwd golf up and down a snowy mountain for years. if you can't do it with fwd and proper fraction equipment (winter tires or chains) then you're dealing with some sort of insane storm you probably shouldn't be driving in
krautstomp@reddit
Personally I like front wheel drive over rear wheel drive in the snow if all else is equal like tires and ground clearance.