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Matt
Matt, Mechanical Engineer
Category: BMW
Satisfied Customers: 22000
Experience:  BEng hons Mech engineering, in auto industry 22 years
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I go skiing Switzerland and drive on snowy roads often. It

Resolved Question:

I go skiing Switzerland and drive on snowy roads often. It is the rule
there to have winter tyres and summer tyres.
I used to have an old heavy BMW X5, and I used it a lot in the snow. It was very steady.
Last year I bought a BMW X5 M50d.
The garage who sold me the car gave me a set of wheels with summer tyres on,
and a set of wheels with winter tyres on.
The winter set they gave me are 255/50 R19,
The summer set of wheels and tyres are 315/35 R20 (rear) and 275/40 R20 (front)
The car was terrible in the snow on the 255/50 R19
I now approach the time to put on the winter tyres again. I understand that
the weight pressing on the snow will be heavier on the narrower tyres, but
that I will get more friction with the wider set of tyres.
Which wheels should I fit new winter tyres to?
Is the problem actually my driving as I notice the torque on the new X5 in first gear is much higher (50% more) than the old X5?
Finally, if it is the torque, I would ideally like to pull away in 3rd gear, but trying this today, the car stops me using 3rd as a 'pull-away' gear. Can I turn this off?
Thanks
Submitted: 1 year ago.
Category: BMW
Expert:  Shantal-Mod replied 1 year ago.
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Customer: replied 1 year ago.
I would like the answer pleasethanks
Expert:  Matt replied 1 year ago.

Hello

in all snow conditions you will be better off with a narrower tyre than normal as this has more bite into the snow , look at rally cars on full snow you'll see they run a very narrow tyre there

I'd say the extra torque certainly will make it more difficult to move off and your strategy of pulling away in 3rd is a good idea and try pressing the DSC button once to disable it in snow as this should then allow some wheelspin and allow you to move

Matt, Mechanical Engineer
Category: BMW
Satisfied Customers: 22000
Experience: BEng hons Mech engineering, in auto industry 22 years
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