Stopping on a Downhill Junction

dgethin · Gate Opener Joined: 05 Feb 2006 Odometer: 10

I have a Suzuki Grand Vitara, I have driven in snow a couple of times, and I have a question.
Where I live there is a steep downhill junction, when there is snow on it, it is very slippy. When I come up to it I am in 4WD, but what do you just the moment before I come to a standstill, if I leave it in gear and brake slightly, I have been known to stall it.
Is there a techinique to be able to stop correctly?

RichardD · Posted: Mon Jan 14, 2013 10:04 am Post subject:

Yes, give yourself much more braking distance and press the clutch just a little earlier and brake more gently!

dxmedia · Mud Obsessed Joined: 10 Dec 2008 Odometer: 2185

4WD does not give you more traction when slowing down or stopping!

simonallen · Posted: Mon Jan 14, 2013 1:22 pm Post subject:

It does when engine braking only...

Ideally in this situation you would want to have done most of your braking before you start going down the hill, so then you have only got to slow yourself down from a lower speed rather than stopping from 40 etc. Engine brake as much as possible as well. Nice low gear and no sudden application of foot brakes etc - be nice and progressive.

DD · Posted: Mon Jan 14, 2013 2:22 pm Post subject:

slow down through the gears where possible......give yourself more braking time if required.

4WD is potentially WORSE in snow going downhill simply because of the vehicle weight and the resultant momentum and therefore force required to stop.

You do get funny looks from some people when crawling downhill in a 4WD vehicle....but these same people are probably BMW drivers who sit in first gear giving it welly when they get stuck.

slow down, use engine braking, brake earlier than usual........and dip the clutch before it stalls Wink

TheClunk · Posted: Mon Jan 14, 2013 3:49 pm Post subject:

TheHeretic · Posted: Mon Jan 14, 2013 5:30 pm Post subject:

scrunt · Posted: Mon Jan 14, 2013 5:44 pm Post subject:

It can be said that the engine braking and the 4x4 effect might assist in retaining traction,
Keep traction whilst reducing or retaining reduced speed and momentum.
Being able to stop when you want, type thing.

Once traction is lost between tyres and surface you are a slege on a downhill slide unless traction is regained.
Getting those tyre turning and regaining traction and then regaining control hopefully.

Certainly that is not always possible with weight, gravity and ice, or snow on ice.
(Mud can be more forgiving in that it can build up under the wheels and help stop you, if you are lucky.)

Being an Auto driver with rear Drum Brakes and no Transmission brake,
i sometimes like the slowing down, low gears and keep the tyres turning and retaining traction.

Sometimes the hand brake is up a notch or too for some drag and slowing down with wheels stiill turning,
& sometimes it is getting pulled on and i will do a hockey stop if needs must.

george

waveydave · Posted: Mon Jan 14, 2013 5:51 pm Post subject:

Tbh if the hill is so steep its hard to control the 4x4 then i dont worry about stalling it. If it helps me stop thats the first goal. Then when i pull off i start it on he starter.

That way no clutch used, no transition of control between sytems so less chance for it to start sliding. If your in low box it wn be an issue. I you ave front anf rear lockers even better.

If the weight does take over then i theory you can start it back up and accellerate and catch up with graity, but then that depends on whats in front of you.

dgethin · Gate Opener Joined: 05 Feb 2006 Odometer: 10

Thanks for all your replies, It has given me something to think about, all we need now is a good layer of snow to try it out!

cynic-al · Posted: Mon Jan 14, 2013 10:20 pm Post subject:

I found when we had the bad ice a couple of years ago you had to be careful when changing down as the engine had that much torque when you dropped a gear instead of the revs picking up to match the speed of the wheels the engine stayed at idle and the wheels slowed to the speed of the engine, the effect was the same as locking the wheels.

All depends on the situation I guess Smile

Does anyone have a link to that video of the fiesta sliding down the hill on its own where the owner jumps out?

scrunt · Posted: Mon Jan 14, 2013 11:09 pm Post subject:

Googled it and ended up watching the Longest WRC Fiesta snow jump.

I like this one.
http://www.youtube.com/watch?v=6249iHSJsKo

w3526602 · Posted: Tue Jan 15, 2013 6:49 am Post subject:

Hi,

Once your front wheels lock, you ain't got no steering.

The first thing you need to do is to lift off the brakes. then re-apply them GENTLY to start slowing down again. If wheels lock again, repeat (which is what ABS does, only more complicated than that).

Engine braking will slow you down, unless the driving wheels lose traction. It seems obvious to me that four wheels braking will give more traction than two, but if the front wheels stop turning, bang goes your steering.
Options then are to depress the clutch, or accelerate, or even change up a gear.

Which leaves you the problem of what are you going to do when you reach the junction.

Nowe would be a good time to identify something soft to hit, this side of the junction, Better to sacrifice your car, than enter the junction in front of a school bus.

It might be best to park your car overnight at bottom of the hill.

602

discosteve · Posted: Tue Jan 15, 2013 12:35 pm Post subject:

w3526602 · Posted: Tue Jan 15, 2013 3:26 pm Post subject:

That's called cadence braking

Hi DiscoSteve.

I knew that, "cadence" may not be in everybody's vocabulary (On another forum, I've just advised a bloke in South Africa that searching for a Land Rover FENDER on a UK website, isn't going to produce many results. He is looking for a pair of front panels, for a Series 2, without holes for headlamps. Anybody?)

I once told Barbara to "get your foot off the ****** brake pedal"

"I caaaaan't!" she replied, as we carried straight on into a hedge, with front wheels locked up.

But she reversed out, and departed the scene before the bis driver had climbed dowb from his cab. Very Happy

602

JoelP · Winch Assistant Joined: 13 Dec 2008 Odometer: 81

If you doubt the grip but have to go down it, then stop at the top, put it in 4wd with difflock if you have, and idle down it in first gear. No brakes and no gas. Intermittantly test grip if you want by dipping the clutch and braking - you have to brake at the bottom, so you may as well find out if its going to stop whilst you are only halfway down, then you have that much more time to grind the kerb or pick a hedge. Equally, when going that slow (idling first gear), you may well be able to pull straight out at the bottom if you can time a gap.

I wouldnt recommend low ratio at all though, its so slow you'd end up touching the gas and all the torque would loose your grip.

Ive headed down a hill in rwd before and even idling the jeep sped up and slid like the handbrake was on - as a previous poster said, a diesel engine can easliy lock the back wheels with engine braking.