Rear wheel drive on snow/ice

[VectraMan]

I think it means you can keep the revs down and stay in a higher numbered gear for longer but still make good progress, without for example havng to change down a gear and floor it in order to get up a snow covered hill, you can instead pretty much cruise up it with hardle anymore throttle input. You can also pull away in a higher numbered gear also. I would imagine snow ploughs have very torquey engines, and the best 4WD's probably have powerful diesel torquey engines.
Revs are an enemy in the snow, and being able to drive the car smoothly with fewer changes in the balance is good (low revs, no heavy braking,less gear changes)

Maybe (and I did stall my petrol car yesterday trying to pull away as slow as possible in second gear), but I think that's more to do with driving style than anything else. Perhaps the diesel driver is more used to being in a high gear and so copes better with snow, but that doesn't mean a diesel is better, rather that the petrol driver hasn't adapated their driving style to snow. Revs and gears don't matter, it's the amount of torque being delivered that counts.

Unfortunately most drivers have little throttle control, which you see all the time in the people who react to a wheel starting to spin by flooring the throttle. And that's never going to work.

Also don't forget that typically diesel engines are heavier. Most diesel engined FWD cars are much more front heavy than the equivalent petrol, and that must help a lot in snow.

[Sysman]

No, think about it. The opposite is true.

More torque means it won't stall at very low revs, so you can take off and drive at low revs and NOT spin the wheels.

I wouldn't set off in second.

When I had a diesel I could set off in the snow without touching the accelerator.

You can also achieve a spin limiting effect with a petrol Land Rover by dropping it into first gear in low range. Think about it - when top speed in that gear is only about 5 mph, there's not much scope for spinning.

I'd always been told that automatics were lousy in the snow, but the first winter I had one I found it great for setting off in the snow - just let the brakes off and let the "creep" do the job for you. The smooth gear changes were probably a help too.

[scooterscot]

No, think about it. The opposite is true.

More torque means it won't stall at very low revs, so you can take off and drive at low revs and NOT spin the wheels.

I wouldn't set off in second.

The XC70 I drive has a winter button, when enabled the car always sets off in 2nd gear.

Surely the Scandinavians can't be wrong?

I would set off in 2nd in this weather every time and use the gear to slow down, and get into the habit of thinking the brake is only used as a last resort.

[Scary]

No, think about it. The opposite is true.

More torque means it won't stall at very low revs, so you can take off and drive at low revs and NOT spin the wheels.

I wouldn't set off in second.

Too much torque will spin the wheels, so you want less torque, not more, which is why it's often easier to set off in a higher gear. It's a good thing if the torque is more controllable, so you can use engine revs and clutch control to deliver *less* torque through the wheels.

[Sysman]

I'm sure an optimum exists depending on size of car and weight. type of drive (RWD/FWD/4RWD), and of course the way the car delivers torque and power (smooth or sudden) etc.

That's correct. As mentioned up thread, the old (proper) Saabs were good in snow and ice, and I've seen an old rear wheel drive Volvo get up steep hills that many a FWD couldn't manage. Swedish manufacturers obviously put some thought into the problem.

Would you believe that I once saw a flat backed Transit bump starting a Land Rover in thick snow by towing it? The trick was that the Transit was carrying an HGV engine carefully placed over the back wheels.

[FarmerPalmer]

When I had a diesel I could set off in the snow without touching the accelerator.

You can also achieve a spin limiting effect with a petrol Land Rover by dropping it into first gear in low range. Think about it - when top speed in that gear is only about 5 mph, there's not much scope for spinning.

I'd always been told that automatics were lousy in the snow, but the first winter I had one I found it great for setting off in the snow - just let the brakes off and let the "creep" do the job for you. The smooth gear changes were probably a help too.

Put auto box in 2 and not D, and it pulls away in 2nd. Press the D3 on the end of the stick and it won't go up into 4th, and will stick to 3rd max, but will stay in 2nd as long as possible is 2 is selected.

Currently have a CRV, previously a Civic Coupe, and they are/were both fine.
Although having the 4WD cut in on the CRV does make a big difference.

neither would redline until 65mph in 2nd, so you can do the whole journey is one gear if you really want to.

[Bagpuss]

I got my S2000 stuck in the snow on a slight incline last year. Wide rear summer tyres, and perfect weight distribution are not good for snow. The S2000 has a torsen diff which means it'll happily spin one wheel, but you can defeat it by pulling on the handbrake, which does work up to a point.

Weight in the boot supposedly does help, but by doing that you're making your car more oversteery which might not be such a great idea. Letting down the rear tyres might help with traction, but also isn't a good thing to be doing.

It's not RWD, it's weight. Snow is one occasion where you're better off having bad weight distribution: i.e. typical FWD, or Porsche. Any proper RWD car has good balance and so is bad at snow.

Wise words, but lets not forget most RWD cars also have a lot of power so need to be driven in bad wether as if there was an egg under the accelerator pedal that you are trying not to break. Many people treat the accelerator like an on off switch. It needs to be carressed, no harsh movements, no harsh braking, for non autos, use the gears to slow the car down. try to stay in high gears (especially when try to get up hills).

I remember having a 1.3 cortina RWD, never a problem in the snow as it had feck all power.

[Diver]

Wise words, but lets not forget most RWD cars also have a lot of power so need to be driven in bad wether as if there was an egg under the accelerator pedal that you are trying not to break. Many people treat the accelerator like an on off switch. It needs to be caressed, no harsh movements, no harsh braking, for non autos, use the gears to slow the car down. try to stay in high gears (just like taxi drivers do).

I remember having a 1.3 cortina RWD, never a problem in the snow as it had flip all power.

But not on a first date

[Pogle]

My RWD is staying put til I can see tarmac again, in the meantime I'll walk or use public transport.

[Bagpuss]

My RWD is staying put til I can see tarmac again, in the meantime I'll walk or use public transport.

I drove a RWD car through that winter of 2003 when people were stranded on the M25 and M11 as the roads weren't gritted. People were spinning FWD cars all over the place yet I didn't. Why? There is one simple rule:

Don't drive the same way in snow.