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What are Snow Chains

Comprehensive Guide to Snow Chains: Buying, Renting, and Fitting

snow chains

Snow chains are quite simply a mechanical device designed to easily fit over a cars existing wheel to offer greater levels of grip on lying snow. The chains are fastened over the driven wheels and ‘dig’ into the snow offering grip, where the tyre was previously unable to grip. We answer some of the most common questions and offer advice and guidance on how to fit snow chains whether buying for your own car or using with a rental car.

What size snow chains do I need?

It’s vitally important that you have the correct size snow chains to suit your car / wheel. Snow chains are designed to fit over a pre-determined tyre size. When buying snow chains check the size of the tyre of your car. This will be displayed on the tyre side wall in the following format;

195 / 65  R15 95V

The numbers relate to the following (in this example)
tyre size
  • 195 = Width - the width of the tyre in mm
  • 65 = Profile - the depth of the tyre sidewall as a percentage of the width, in this case 65% of 195mm = 126.75mm.
  • R18 = Radius - the DIAMETER (not the radius) of the wheel in inches
  • 95V = Speed/Load Rating - the maximum designed speed / load rating

Do you need to put snow chains on all four wheels?

The short answer is no, however if you have 2 sets of snow chains then it’s useful to have on all 4 wheels to give optimum traction when driving in snow. The key thing to remember is to fit the snow chains to the driven wheels of the car. If you’re renting a car, or unsure which are the driven wheels you can easily check by seeing which wheels are spinning if you are stuck in snow / on ice. As a general rule of thumb, the majority of cars in Europe are front wheel drive with the exception of most BMW and Mercedes models. In the USA, rear wheel drive is more common.

Do you need snow chains on a 4x4?

In short, yes. Whilst 4 wheel drive is excellent for driving in snow (and any low grip conditions), ultimately you still have tyres acting as contact patches with a very low friction surface so no matter whether front wheel drive, rear wheel drive or 4 wheel drive, if the tyres cannot grip the road surface (in this case due to snow), the number of driven wheels won’t make much difference. If you are fitting snow chains to a 4WD car, it’s recommended you fit a set to ALL wheels, however if you only have 1 set of snow chains, it’s recommended that you fit them to the predominant driven wheels (in most cases, the front wheels).

Do you need snow chains with winter tyres?

Much like whether you need snow chains in a 4x4, in extreme conditions winter tyres may not be sufficient to drive safely on snow. In such instances it’s recommended to fit snow chains over winter tyres in exactly the same way you would over regular tyres.

Snow chain laws – Is it legal to use snow chains?

In some locations you are legally required to use snow chains in certain circumstances and in many locations you are legally required to carry them in case they are needed. See our guide to where you need snow chains in Europe for more information.

There are no specific laws in the UK governing the use of snow chains, they can be used where appropriate and conditions dictate. Much like many winter driving laws, you could be prosecuted under umbrella laws concerning ensuring your car is road worthy and fit for purpose. For example, in the UK you are more likely to be on the wrong side of the law if using snow chains when NOT appropriate as opposed to not using them when it would be beneficial. In parts of Europe however where lying snow is far more common, it’s wise to carry snow chains in the car and know how to fit them as at times you may be legally required to have them fitted. If renting a car in a winter destination you may be offered snow chains as an optional extra. If they are a legal requirement they will be included with the rental, much like the car hire winterisation fee.

Max speed with snow chains

The maximum recommended speed for driving with snow chains will depend on the make and model of the snow chain itself. You should refer the owners manual / installation guide for the particular snow chain you are using. It is however generally not recommended to drive more than 50kph / 30mph with snow chains fitted. Snow chains are only to be used in extreme snow conditions where it’s unlikely that you’ll need or want to travel at speeds in excess of this. If you do exceed the recommended maximum speed, or drive on roads with no snow cover you are likely to damage the chains which could lead to them failing and causing damage to the rest of the car / tyre.

Braking distances will be affected by snow chains also, whilst braking in snow can take up to 5x longer than in wet conditions, braking distances with snow chains where no lying snow is present are likely to be longer than without snow chains as the chain itself will obstruct the braking surface of the tyre and the road.

Should I buy snow chains or snow socks

Much like many things in life, you get what you pay for and it depends on their intended use. For very occasional use, snow socks offer a great low cost alternative to snow chains, however they don’t provide the same level of performance or durability as a snow chain. Snow chains start from around £60, similar to snow socks, however this is the very budget end of the spectrum and high quality items are likely to cost in excess of £200, at this point a snow sock for £60 makes a good argument for itself.

You wouldn’t want to drive far with a snow sock fitted as it would wear quickly and is easily damaged, however for emergency use it could get you out of a tricky situation and is easy stored in the car.