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Manual transmissions great for ice

I live up in the icy north, about halfway up Vermont. And I've come to love my automatic transmission for bad-condition winter driving.

Every year or two, the roads get bad, fast, typically when heavy freezing rain is followed by light powdery snow. About 5 years ago, a sudden 10 degree drop in temperature lead to 13 accidents in 1 town over the course of 10 minutes. More recently, a semi jackknifed when the highway iced up suddenly. I've seen cops struggle with just *walking* on the roads.

In these conditions, you've got to carefully regulate your speed, and you've got to rely on engine braking (I once briefly lost control by tapping the brakes at 5mph).

And when you need to do this, a manual transmission is wonderful. You just stay in the first three gears, relying heavily on engine braking and clutch abuse. It's probably not great for your engine, but it's far better than totalling your car in a ditch, or going into an uncontrolled spin.

With an automatic, you usually only get two manual gears--and no clutch. I'm not going back to an automatic unless I move someplace warmer.

J. Random Hacker
Tuesday, August 24, 2004


An automatic can be driven in first gear. Just don't try to go over 20 MPH.

Some new cars have automatics where you can actually select the precise gear, just like with a manual.

frustrated
Tuesday, August 24, 2004

How about an auto-trans with ABS/Traction control.

That'll work far better than anything you could do with a standard. No offense to you; just assuming you're human ;-)

Tim
Tuesday, August 24, 2004

Everyone, no matter what kind of transmission they have should practice driving on the ice.

What I did was, whenever it was icy and I had to drive, I'd find a wide, empty street and drive sleightly too fast (15 mph is probably too fast) and then slam on the brakes and try to recover. I was 100% sure there were no obstacles nearby, and nobody to hurt.

It taught me a lot about "braking and pumping" and how my car handled on the ice, and about ice in general. I didn't have ABS on this car. My next car will have ABS and probably some form of 4wd/traction control.

Engine compression is great, but it won't stop you when a kid jumps out in to the road.

www.MarkTAW.com
Tuesday, August 24, 2004

Also to note.  In snow you will many times get through more by using a higher gear at speed x because you will have less torque and don't spin as easily.  That said the Subaru Outback with AWD and an automatic does just fine.

Malloc
Tuesday, August 24, 2004

Also a good point. During one blizzard when the snow was around 3-4 feet (about a meter to you europeans), and I didn't move the car for about 3 days, it took the extreme "Low Gear" setting to get it moving. Then there was so much power I couldn't get the thing to stop, even at the 1-2mph crawl it idled at.

I was getting out of a parallel parking situation, so the slow creep foward would've hit the other car if I wasn't careful.

I'm not talking about first gear, I'm talking about the low 4wd setting that radically changes the gearing ratios for things like towing, climbing over felled trees or creeping along on the ice.

I'm sure having a less drastic version of this in a manual transmission would be good.

www.MarkTAW.com
Tuesday, August 24, 2004

All the ABS/Traction control in the world isn't going to get you to stop on ice fast enough not to hit a kid who jumps out at you. There's not enough friction, even if you use all of it.

I have the worst car for winter driving. A manual transmission, rear wheel drive, convertable. Good thing I live in California. It's a blast to oversteer around cornsers at 20 mph in the wet when theres no one else on the road.

Miles Archer
Tuesday, August 24, 2004

If that's the case, then you're driving too fast. I've found I could stop very quickly just by pumping the brakes. Surprisingly fast. It's amazing what regaining traction and then braking again will do. This is what ABS is supposed to do, but hundreds of times a second.

www.MarkTAW.com
Tuesday, August 24, 2004

I've never used a really high-end traction control system--I tend to buy inexpensive, late-model used cars because of how fast vehicles rust around here. And not having used such a system, I can't tell you how good it is.

I *do* know that anti-lock brakes have trouble in conditions where even tapping the breaks is unsafe (I once wrecked a car this way--there were already two pickups in the ditch when I went off the road).

I most appreciate the manual transmission when I'm doing 40mph in 3rd on an interstate, and realize I *really* want to be doing 5mph in 1st. Some slow, cautious engine braking seems to be the safest way to do this.

You do this very much, you need to buy a new transmission. But transmissions cost less than entire new cars...

J. Random Hacker
Tuesday, August 24, 2004

Yeah, if ABS fails, you're probably driving way too fast. But "way too fast" may be 40mph on a straight, utterly deserted interstate which suddenly turns out to be covered in snow-dusted black ice.

In this case, you want to slow down *gently*--you've got plenty of time, but anything that breaks tire traction for an instant is undesirable.

Nobody likes driving in this weather, but sometimes you're in the boonies, an hour from home, and the weather has turned foul. You can't go 5mph all the way. Bridges and hilltops are the two most-likely spots to suddenly encounter ice.

ABS is, of course, absolutely necessary for fast stops. My winter driving prescription: ABS, snow tires, AAA, a bag of rock salt, a shovel, heavy blankets, a cell phone, common sense--and a manual transmission. :-)

One of my friend's parents went further: When he was in high school, they signed him up for an all-day lesson in ice driving. I've watched him show off in empty, icy parking lots; he's able to throw his car into a spin and wind up exactly in a parking spot. Probably an excellent investment for anybody with teenage kids in a northern climate.

J. Random Hacker
Tuesday, August 24, 2004

"I most appreciate the manual transmission when I'm doing 40mph in 3rd on an interstate, and realize I *really* want to be doing 5mph in 1st. Some slow, cautious engine braking seems to be the safest way to do this."

...and brakes cost less than entire new transmissions ;-)

Tim
Tuesday, August 24, 2004

Yeah but if you hit the brakes you end up in a skid. You'll lock up the wheels and lose traction.

www.MarkTAW.com
Tuesday, August 24, 2004

and if you downshift too suddenly, you'll do even weirder things than hitting the brakes too hard.

mb
Tuesday, August 24, 2004

ahh yes compression lockups, they are even more fun on a bike

Dan G
Tuesday, August 24, 2004

You blokes obviously know what it's about. I had a boss who grew up in Chicago and then lived in Memphis before his spell in Oz - he reckoned the worst combination was ice and Tennessee drivers, it didn't happen often enough for the locals to practice.

Here in Melbourne it's 19 degrees and sunny despite there being more snow in the hills than we've seen for a decade -after carrying roadchains (compulsory on some ski access roads) all that time without needing them, it's just possible they will be required once or twice more . Snowdriving is a dying art here as the world warms up.

{about a meter to you europeans],  Er... that would be a metre... check your phrasebooks before boarding.

trollop
Tuesday, August 24, 2004

er, that's 19 deg Celsius, say 66 in old money.

trollop
Tuesday, August 24, 2004

So do we have a definitive answer or not?

www.MarkTAW.com
Wednesday, August 25, 2004

Yes - transmission type is a matter of personal preference.

a cynic writes...
Wednesday, August 25, 2004

My automatic transmission has a special "snow mode", which I have engaged a few times when I used to visit the frozen north of the UK.

It seems to work really well, although I don't really want to test it too far ;-)

Nemesis
Wednesday, August 25, 2004

My wifes car has electronic traction control. Great for getting out of the garage under the house after a nights' snow (40% slope). the car just sort of snuggles itself up the ramp (hard to explain if you have never seen this in action. Each wheel seems to independently take little "steps").

Just me (Sir to you)
Wednesday, August 25, 2004

forget the transmission, its all about having proper winter tires.

Kenny
Wednesday, August 25, 2004

The funniest thing i ever saw on ice was over in Berkeley. The UC campus is build on the edge of some decent sized hills. It rarely gets cold enough to freeze. However, once it did. and sensibly they closed all the roads. However, a cop thought that was just for civilians and drove his car up the hill near the football stadium.  About halfway up, he lost traction and bounced off a house on the way back down.

Miles Archer
Wednesday, August 25, 2004

>About halfway up, he lost traction and bounced off a house on the way back down.

Good one! Around here, we use the term 'road curling' to describe what happens on the streets after the first snow of the season. You'd really think that after driving ice and snow covered roads several months a year for 20 years would translate to a careful reaquaintance with the necessary techniques.

For those of you with even passing knowledge of curling, think of the intersections as the 'house'.

Ron Porter
Wednesday, August 25, 2004

Had to duck off to a wiki to brush up on curling.

Looks like lawnbowls with SUVs.

trollop
Thursday, August 26, 2004

Okay, maybe I'm missing something here, but how exactly does engine braking differ from brake braking?  Don't both methods have the same effect of slowing the wheels, except that engine braking is less responsive (since you have to stomp on the clutch, move the stick, then carefully re-engage the clutch)?  Or is there really that much difference between tapping the brakes, which slows all four wheels, and using a multi-thousand-dollar transmission to do the job of $100 worth of brake pads?  (=

Sam Livingston-Gray
Thursday, August 26, 2004

engine braking = no chance of wheels locking up if you lose friction

Kenny
Thursday, August 26, 2004

You can accomplish the same thing as engine braking with cautious use of the e-brake.  It only slows down, and potentially skids, the rear wheels, leaving the front wheels free to steer.
Obviously this is going to work much better with a hand-operated e-brake than a foot-operated one; because of the racheting action you need to keep pressure on the release at the same time.

IowaViaTx
Tuesday, August 31, 2004

(and yes, you can skid while engine braking...)

IowaViaTx
Tuesday, August 31, 2004

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