Member Since: 05 Feb 2006
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Not seen a reason written down but when I asked a LR guru (part of their 'vehicle dynamics' team) he said it was due to the change in effective rolling diameter being close to or outside the range permitted by the 4x4 system. As a result the electronics and diff would be fighting the chains and may cause damage to the diff and work the DSC/brakes too hard.
Apparently the tolerance on the front diff & DSC is much larger to allow for steering, whilst the sensitivity on the rear wheels is high as the vehicle's natural balance would see the rear end break free a lot earlier than would be desirable. The same issue also makes the car much more sensitive to a small reduction in rear tyre PSI, such as a slow puncture, than at the fronts. As a result, it will typically activate the DSC and warning lights when negotiating an average bend or roundabout with a relatively small pressure drop.
In sum, the car micro-manages the rear-end and adding chains would mess things up.Land Rover - Turning Drivers into Mechanics Since 1948
Robbie...Absolutely no idea what any of what you wrote means but brillant answer Snow chains stay on the front (as I thought).
29th Dec 2011 4:06 pm
cold_n_wet
Member Since: 05 May 2009
Location: Bergen
Posts: 1509
I have only every used snow chains on the font, OK I have 17" on, but even if I had 19" on for the winter they would go on the front, reason being if you need chains for grip, then being able to steer is a good idea.
There was som clearance issues with 19" and some chain manufacturer, but maybe the electronics would through a wobbly, then just turn off spesial programs and DSC.
In the deep slippy stuff to my cabin, I use sand mode, high range, extended mode to get me up, this works for me, I did turn of DSC one time up as I felt it kicking in and cutting power.
I have noticed that the rear diff locks before the senter, and that the back diff locks with the senter difflocking.
I assume that the front wheels have traction (have chains on) and the rear wheel spins easier.
I am serious considering chains for the back too.
I dont know why Land Rover don't recomend chains on the back at all, should be good clearance.
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29th Dec 2011 4:56 pm
J@mes
Member Since: 10 Nov 2008
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Thanks Robbie 2014 D4 XS
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29th Dec 2011 5:14 pm
AndyViking
Member Since: 09 Aug 2007
Location: Kent
Posts: 269
I spent a lot of time last year looking into chains etc for just the same reason - going to France and they are a legal requirement in the Alps.
I run Grabber AT2s at 255/55 x 19 and you need to be careful with the tyre profile. At the edge of these tyres the profile is much "squarer" than stock tyres, so normal chains don't fit. You also need to be very careful with the 19" rims to avoid fouling the steering gear - the "spider" type chains are much better for this as they do not go behind the tyre / rim.
I spent hours with the Snowchains guys, and even consulted Konig in Italy, and they came back and suggested the K-Summit XL by Thule or the Konig equivalent. Not the cheapest by a long long way, but they are so easy to fit in the snow and on a cold, icy mountain side that is what you want.
A word of caution - make sure you get the right size of adaptor to go on your nuts ( ) as the standard one is the wrong size for a D3 and I spend ages trying to find the right size of adaptors in the UK. Snowchains chould be able to porvide the right one, but were out of stock when I bought my chains.
Also, do as others have suggested and do a trial run or three BEFORE you go. Snow chains such as the K-Summits are adjustable and you want to do all this before you leave - I ended up taking all three adjusters out of the chains to get them to fit properly when the handbook said they would fit "out of the box" - again, the tyre was the difference.
Hope this helps?D3 - 2008.5MY HSE, Stornaway Grey, RSE etc - all the toys
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5th Jan 2012 4:56 pm
DiscoStu
Member Since: 09 Apr 2006
Location: London
Posts: 11412
Used chains on all 4 wheels (Pewag on 19") on the Croisiere Blanche a couple of years back. Mostly offroad too. No issues. Had to use spacers for clearance though.Disco 5 HSE Lux
https://www.youtube.com/watch?v=peyiqaJrmMU
....going to France and they are a legal requirement in the Alps....
Thats twice this has been said. I don't think it is the law. It is best practice etc, etc....however care to confirm where it says it is the law to have snow chains in your car in the French Alps?
5th Jan 2012 6:43 pm
Robbie
Member Since: 05 Feb 2006
Location: ¯\_(ツ)_/¯
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I cannot recall it being a law, but when the conditions require it I have seen 'the law' stop vehicles from attempting the more challenging bits unless they have snow chains fitted or with them. In everyone of these situations they have waived proper 4x4 owners past the check points and I have never needed or been asked to produce chains.
Seemed a pretty sensible way of managing things as the police targeted the rear-wheel drive cars first and ensured that things kept moving. No doubt one of the forum residents from France can clarify the actual law.Land Rover - Turning Drivers into Mechanics Since 1948
As I said before its not 'the law' to have snow chains in the Alps in France as has been said here twice. Yes, 100% it is best advice but not the law.
5th Jan 2012 10:05 pm
buzz569
Member Since: 09 Nov 2010
Location: Midlands
Posts: 16
I get the logic of fitting the chains to the front from a steering perspective but I still don't understand why fitting them to the rear would cause any technical issue. It's a vehicle designed for use in situations where grip may be variable under each wheel and has systems designed to cope with this. If the chains were fitted to the rear and hence had more grip surely the traction control would control the front end in a similar manner as if you were driving on snow with no chains on?
I have Konig XG 12 Pro chains which fit fine on the front of 19" wheels with (just) acceptable clearance to the suspension upright but had considered fitting them on the rear, where there is loads of clearance, should the need arise for a short distance at low speed. That said, in the Alps last year there wasn't any situation on fairly well cleared roads (on standard Scorpions) that made me feel I would have to get the chains out of the box!
17th Jan 2012 4:24 pm
Bushwanderer
Member Since: 27 Nov 2007
Location: Northern Rivers, NSW, Australia
Posts: 2050
Why would the chains have more grip on the rear?
Why be so dismissive of the importance of steering?The Bearded Dragon
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good reply.
Snow chains stay on the front (as I thought). 
) as the standard one is the wrong size for a D3 and I spend ages trying to find the right size of adaptors in the UK. Snowchains chould be able to porvide the right one, but were out of stock when I bought my chains.
