Snow chains - fronts only?

[Hawkwind]

Living in the hills, and with a drive to work that takes me over the Pen y Fan pass (highest mountain in Southern Britain), I'm kitting out my Scout with winter gear in case it's another harsh winter.

 

I'm heeding Skoda's advice in the driver's manual and will be putting 205/55 R16 winter tyres on a set of 16"x 6.0J 5x112 ET50 alloys. So far so good.

 

The manual also states, in bold type, that "snow chains must only be mounted on the front wheels". This seems to fly in the face of the general opinion that snow chains should be attached to all 4 wheels on a 4WD. 

 

Setting insurance issues aside, is there a good reason why Skoda's advice should be adhered to with a Scout? I've checked previous threads and haven't found a definitive answer to this, although I may have missed it.

 

[Phil-E]

Winter tyres themselves will make a MASSIVE difference. I'd be very surprised you would need chains at any point with winter tyres on - they really are staggeringly better than normal tyres.

 

Having said that chains may be needed to get up very steep snowy hills.

 

I would think that as the Octavia doesn't have a full time 4wd drive system that it isn't necessary to fit to the rear too. Power will only be sent to the rear wheels if the front aren't getting traction. With the snow chains on they WILL get traction (even up steep 20%+ inclines they are light driving on dry tarmac) so the rear wheels won't even be given any power.

 

Then as you will have winter tyres on the rear you will still have grip for cornering and should they need to turn to assist you up a hill.

 

An alternative might be snow socks. I've heard they are easier to get on and off and they're not as noisy while driving and have a slightly higher speed limit.

 

Phil

[Phil-E]

Oh and I have experience of a 4wd in winter with just winter tyres on.

 

My other halfs uncle has a Touareg 3.0 TDI. I believe it's also a haldex 4wd (so not full time). With just winter tyres on there are no hills we could not get up.

 

They live in a hilly wooded area. Their house is up a 25% slope. We needed our snow chains on to get up in our Peugeot 306 1.9 D even with winter tyres.

 

But the Touareg although the fronts slips initially as you hit the slope the rear wheels kicked in and it was like a train up the slope. I imagine the Octavia will have similar capabilities.

 

Phil

[Ootohere]

You do not have a 4x4, you have a part time AWD. (But you still want to be running the same Total Diameter front and rear.)

So if you do fit Snow Chains fit them on all 4 wheels if you are going to be driving any distance on White Hard Packed Snow or Ice even Softer deeper snow.

But seeing as you will not be driving on Black Top roads with Snow Chains on, (not only not safe but illegal in the UK,

well Police in some areas will try to say it is,

but only usually where they are stuck in unsuitable vehicles)

 

Maybe worth only fitting a Pair to the front drive, steer, brake wheels to get you extracted from a situation where you can not get traction, since putting them on and off is not quick or that easy at a roadside once the traffic is moving. (Maybe Snow Socks for putting on for short distances on ice would be a better option.)

so  maybe 4 chains for all tyres, on and off are not necessary unless staying on Roads that are Unploughed and closed to normal traffic and covering some distance or leaving them on for using over several days of White Top Roads.

 

Even with Winter Tyres / Chains Fitted and a Scout with part time AWD the clearance is not great and getting through deep snow or drifts 

is not going to be that much better than cars like older Ford Fiestas or Fiat Pandas on Winter tyres. 

 

You get times where Chains are just not going to help.

& On off, On off is a PITA, where just fitting the correct tyres is so much easier for some areas of Britain.

** Nights are drawing in, getting excited and ready for some good snow falls this winter.**

[Huskoda]

A few things wrong in the answers here.

Haldex works all the time. Only the very early versions dumbly waited for slip, version 4+ (and 2 to a lesser degree) use various sensors and inputs to determine the appropriate torque distribution. Such as throttle position and inclination. If you're putting your foot down facing uphill, it will be sending power to the rear without waiting for tyres to spin. Now, chains will work on the front axle as it mechanically does not work like a vehicle with a centre differential, as it does not have one. The front diff is permenantly connected to the gearbox output all the time, so the front wheels will always be powered regardles and the torque will be steady, controlled and easier to work with. That is why I think it says only use the chains on the front. If you're in severe enough conditions that require them you want the car to behave predictably.

Touaregs also have longitudinal engines and Torsen centre diffs. Haldex is a mechanism used to add AWD to transverse engined cars only.

Though Phil is right and winter tyres alone will make a massive difference, especially when added to AWD.

[Ootohere]

You will always be needing tyres for every trip.

Snow chains might never ever need to be carried or fitted unless travelling in some other EU Countries.

http://briskoda.net/forums/topic/336572-how-good-is-the-scout-4-wheel-drive-system

post #29 covers the systems well, there are no locking diffs, so AWD can become 1 wheel drive or even no traction no wheel drive, just like with all vehicles, and even chains on ice unless digging in can have the drive wheels spinning.

[Hawkwind]

Thanks guys, very helpful info, I've learnt a lot.

 

Re: the legality of snow chains, Halfords say "they are perfectly above board - as long as they are fitted properly."

 

Granted they probably have a good margin to protect on their snow chain range, but guidance on winter driving does seem to be a weakness in the Highway Code. This is reflected in sections 228-231 on gov.uk.

 

Given that I've never used winter tyres before I'm wondering how I've managed to reach my 60s in one piece. I think I was spoiled by having a 2CV (with normal tyres) in my early 20s, which made driving in snow exceptionally good fun. Or maybe it was the drugs.

 

The discussion so far leads me to abandon the idea of buying 2 pairs of snow chains (saving a good few quid), and to get one pair for the fronts when I need a bit of extra help to get up the steep track to the house.

[dbg400]

Lidl do snow chains on offer every year, and I bought a set that fit 205/55/16s for the grand sum of £19.99. Other than a test fitting they haven't been out of their case as my winter tyres have easily coped on the few days we've had snow since getting the Yeti. I've been up a few steep slopes than had stopped both 2 & 4 wheel drive vehicles on summer tyres, so I think the chains will remain unused!

[Huskoda]

I appear to be wrong. Snow chains are legal here, you just can't use them on clear roads. It's studded tyres that are not

[Ootohere]

Studded tyres can also be used on ice covered roads, roads closed to vehicles other than 4x4's or for access only.

After all sometimes someone needs to go and recover vehicles that slid off the roads on the ice.

There are places in the UK with public roads that can stay covered in ice for many days and do not get treated.

 

Easy enough when necessary to put a couple of dozen studs or more into the drive wheels when you have suitable tyres when needs must with a powered screw driver, and then remove again if the vehicle needs to go onto blacktop without an ice covering.

Not so common these days, but then unless you are there when someone is doing it you are none the wiser, as many officers of the law are not unless they are moving around in suitable vehicles.

[Jevpls]

I live in country where winters are very harsh and I have NEVER seen anyone using snow chains (they are legal, though). People simply use proper winter tyres and they can be extremely different to all-season or summer tyres (useless in winter, actually). Soft rubber, rought tread and maybe studs (for ice) - that's what do you need.

With 4x4 and winter tyres you will be able to get anywhere you wish. OK, very steep hills and abandoned rural roads may be the exceptions but mostly it should be fine without any chains.

 

Last year I bought Michelin X-ice XI-3 winter tyres and I'm very satisfied. They work properly in all conditions (in winter of course ) except wet ice. Nothing works well on that except maybe studs...

[Jelibeli]

I ran winter tyres through the winter on my last car for three years, and the first year it snowed very, very heavily.  On my journey to work, a lorry crashed on the motorway and I had to take to untreated back roads instead.  There were many abandoned cars, the only things moving were me & a dustcart.  And it was such fun, too!

 

I change to winter tyres every November (they are better than ordinary tyres for any temperature below 7C), and while my economy slips a little, my car never does.

 

As for front / rear, I would always fit a full set of winter tyres, as having less grip on the rear drastically increases the chance of your car swapping ends if the front bites under braking and the rear doesn't.

[S4Dane]

I've driven to the Alps about 5 times now over the past 2 years and I haven't had to use snow chains once.

 

Just TorSen 4wd and snow tyres, this year I took my S4 which had Michelin Alpin winter tyres and the year before I took a C5 Allroad which had come with the cheapest of winter tyres you can buy.

 

I haven't struggled even slightly yet and the most recent time in the S4 it was dumping a metre of snow as we arrived and started to drive up the mountain - it doesn't really get much more difficult than that. Even the cheapest of winter tyres make a huge difference.

 

Snow chains on the front wheels only in a Haldex equipped car makes sense because generally most of the power will go through the front wheels. If I ever have to use snow chains my manual says to apply them to the rear of the car, i imagine because that's where most of the power can get sent. Snow chains on all 4 wheels is something I've never seen or heard of and seems like massive overkill - The front wheel drive cars driving up the mountain in the snow dump were only using chains on the front of the car.

 

 

[Aspman]

Snow socks might be an option if you don't want to go the whole hog with tyres.

 

But a bit like chains you're supposed to take them off when the road surface starts to appear again but they won't damage the road they'll only damage themselves.

 

Snow tyres are probably the best option since they will deal with low temperatures and ice where as chains only work on deep packed snow.