Auto gearboxes in the snow

[Chris71]

Just how bad are slush boxes (pun sadly intended) in the snow? Am I right in thinking a lot of cars come with a snow mode (which presumably just locks up the torque converter in a low gear)?

[anonymous-user]

1. Get in car
2. Drive the car

It's exactly the same as any manual car. If you want to limit torque at the wheels, just move off in second gear. As I said, it's exactly the same.

[kambites]

Chris71 said:

Just how bad are slush boxes (pun sadly intended) in the snow? Am I right in thinking a lot of cars come with a snow mode (which presumably just locks up the torque converter in a low gear)?

Snow mode will force the gearbox into a high gear. Usually third, I think?

[Baryonyx]

They usually have D and a 'lockout' function. My Audi A8 has D-2-3-4 and a tiptronic function. I've not had any problems in the snow, really. Nothing that a manual transmission would have solved, anyway, though I do vastly prefer manuals.

[scotty_d]

My auto is great in the snow but 4wd does seem to help alot along with AT tyres

[Liquid Tuna]

I'm not convinced they are the same. I have auto and manual cars and prefer a manual in the snow. Maybe it's psychological and a mental feeling of more control over the car, but the auto never seems as quick to respond to smaller inputs you'd give a clutch. There's also the fact that there's still drive to the wheels even when your foot is off the accelerator when in D or any other gear and working against the brake.

[Coolbanana]

Automatic LR's - and many manuals for that matter - have a Terrain Response system so, yeah, press a button and 'snow/gravel' mode is engaged. The car then does magic and you have all the traction you need.
Same with some new Jeep's and Fords.

From what I understand, this setting boosts traction control and ABS brake performance. The transmission starts in second gear (3rd in low range I think) shifts are quicker and throttle response is dampened. This is for hard-packed slippery surfaces. If the snow is deep, I believe 'sand' mode is best.

Of course, you can drive 'manually' too with modern LR's using the paddle-shifts.

Edited by Coolbanana on Wednesday 23 January 14:57

[thinfourth2]

And no break in torque when changing gear so in some ways they are preferably

[Garvin]

Coolbanana said:

Automatic LR's - and many manuals for that matter - have a Terrain Response system so, yeah, press a button and 'snow/gravel' mode is engaged. The car then does magic and you have all the traction you need.
Same with some new Jeep's and Fords.

From what I understand, this setting boosts traction control and ABS brake performance. The transmission starts in second gear (3rd in low range I think) shifts are quicker and throttle response is dampened. This is for hard-packed slippery surfaces. If the snow is deep, I believe 'sand' mode is best.

Of course, you can drive 'manually' too with modern LR's using the paddle-shifts.

Edited by Coolbanana on Wednesday 23 January 14:57

I have an 'old' automatic Range Rover without all the modern day TRS 'gizzmos' and there's not really anything that stops it. It does, of course, have low ratio but I only ever need to engage that in the snow when recovering other vehicles from their various predicaments.

As for traction, no amount of clever hardware and software can alter the traction between tyre and surface and a suitable 'bog standard' traction control system can provide all the help ever needed. The TRS systems really do just help overcome the limitations of the driver.

[sjg]

5 USA said:

1. Get in car
2. Drive the car

It's exactly the same as any manual car. If you want to limit torque at the wheels, just move off in second gear. As I said, it's exactly the same.

I can't find a way to force my DSG box into second at a standstill (and it doesn't have anything like a snow mode). Other than that, agreed.

[kambites]

sjg said:

I can't find a way to force my DSG box into second at a standstill (and it doesn't have anything like a snow mode). Other than that, agreed.

I'd guess they're paranoid about killing the clutch if they let you pull away in high gears in a clutched automatic. "Slipping" a torque converter doesn't do it any harm.

[fangio]

DSG = fan-bloody-tastic!

[domster]

Most gearboxes seem to miss the old 'Winter' setting now, presumably because the box ECU makes its own allowances. Probably looks at wheel slip, temperature, incline and then works out it is on slipperier stuff and goes into a winter mode accordingly.

My old E46 auto runs pretty well in the snow, it seems to choose lower gears for longer than going for higher ones though - maybe to maximise engine braking so you don't have to touch the brakes so much. That said, I prefer a manual as you do feel more in control.

[sparks_E39]

My steptronic E39 is best like this:

Manual mode (full 5 gear selection)

Select 2nd

Traction control off

Drive according to the conditions.

[LotusOmega375D]

I think the OP is stuck in a snowdrift....

http://www.pistonheads.com/gassing/topic.asp?h=0&a...

[Fire99]

My Jeep Cherokee was great, though that would be due to tyres, 4wd, low ratio box etc etc rather than the simple Auto box itself.

[AJB]

I put this on another thread earlier but:

To me the the biggest disadvantage of a RWD auto in the snow is that when it's really slippery, the fronts lock up on gentle braking, but the gentle braking isn't enough to stop the driven rear wheels pushing you forwards. So the 'creep' becomes an 'unstoppable creep with no steering'. Somehow my brain finds it hard to brake harder when the fronts are locked and I've got no steering.

I've now learnt to knock an auto into neutral when approaching any kind of a give way or stop situation, and it works a lot better!

[Simond S]

Biggest issue with Auto in the snow is the engine is always pushing you forward. Braking then becomes harder and the brakes more likely to lock / ABS cut brakes off.

HDC is a godsend that i am very glad to have, I also use the cars in manual mode not full auto in slippy conditions.

[bigdom]

BMW e38, no problem at all in snow, just left in full auto mode. Does have 16" winter tyre/wheel combo on, rather than summer 18's

[Fire99]

AJB said:

I put this on another thread earlier but:

To me the the biggest disadvantage of a RWD auto in the snow is that when it's really slippery, the fronts lock up on gentle braking, but the gentle braking isn't enough to stop the driven rear wheels pushing you forwards. So the 'creep' becomes an 'unstoppable creep with no steering'. Somehow my brain finds it hard to brake harder when the fronts are locked and I've got no steering.

I've now learnt to knock an auto into neutral when approaching any kind of a give way or stop situation, and it works a lot better!

Good point. I've experienced that one myself.