Slick hill...neutral or low

Michael Dye

New Graham Knives
Dealer / Materials Provider
Joined
Nov 26, 1999
Messages
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Ongoing question this time of year in the mountains....when going down a slick snow covered (or icy) hill....do YOU kick it in neutral, or go to lower gear?
What say you?
 
Lower gear, in my experience, sometimes you have to give some very slight acceleration to regain control in a slide.
 
Right. "Engine braking" is generally safer on a slick downhill that trying to ride the actual brakes, and you have the ability to use power if necessary.

Going up slick hills requires momentum and an educated throttle foot.
 
Ride the gears down the hill. Doesn't work every time, but it works a heckuva lot better than riding the brakes.

Example, last year I was driving an army surplus deuce-and-a-half down a very steep and slippery back road in Colorado. Six-wheel drive, low range gears. Doing pretty good most of the way, until the back started going faster than the front...
 
Low gear for me. Not super low, you don't want the tires to lock up from engine braking, but low enough to slow the vehicle without sliding.
 
Drag your feet like Fred Flintstone.:D.:D...But keep it in low gear.
 
There's an art to winter driving that will only come with experience. It's all dependent on the ability of your wheels to get traction, and that can vary from top to middle to bottom of the hill. Very generally speaking, in gear is better, but, the engine braking effect experienced in gear can cause the front or rear wheels to slide if they hit ice or excessively slippery snow/slush. If that's the case, experience will tell you whether to hit the clutch or give it some throttle to pull the front end in the right direction.

All this varies even further depending on whether or not you have front, rear, or four wheel drive, and whether you have posi' or not.

Start with small hills, bracketed by shallow ditches and no trees and get used to what can happen. Or, get jiggy in a mall parking lot after dark, getting to grips with how your vehicle moves when it loses traction.

I saw a utilities truck going down a hill once with his wheels periodically spinning in reverse. He either totally knew what he was doing, or he just lucked out while trying what looked to me like a crazy-ass maneuver. Either way, it worked for him.
 
Live in the South. What is this ice that you speak of? Nevermind scratch that stay where you are we've got enough ice bound yankees headed this way as it is... ;)
 
Live in the South. What is this ice that you speak of? Nevermind scratch that stay where you are we've got enough ice bound yankees headed this way as it is... ;)

The problem with you southerners is that when it does snow (less than 1") no one knows how to deal with it...We Yankees love it;)
 
The worst ice conditions I've driven in were in Arkansas' Ozark Mountains. No snow, just sheets of ice covering everything. Combine the ice with steep curving hills and no winter road treatments.

I know the Ozarks are not in the Deep South, but it's still technically the South.
 
There's an art to winter driving that will only come with experience. It's all dependent on the ability of your wheels to get traction, and that can vary from top to middle to bottom of the hill. Very generally speaking, in gear is better, but, the engine braking effect experienced in gear can cause the front or rear wheels to slide if they hit ice or excessively slippery snow/slush. If that's the case, experience will tell you whether to hit the clutch or give it some throttle to pull the front end in the right direction.

All this varies even further depending on whether or not you have front, rear, or four wheel drive, and whether you have posi' or not.

Start with small hills, bracketed by shallow ditches and no trees and get used to what can happen. Or, get jiggy in a mall parking lot after dark, getting to grips with how your vehicle moves when it loses traction.

I saw a utilities truck going down a hill once with his wheels periodically spinning in reverse. He either totally knew what he was doing, or he just lucked out while trying what looked to me like a crazy-ass maneuver. Either way, it worked for him.

i've done this before in a 2wd automatic truck :D

i used to downshift to slowdown on ice since i could then still steer with the front wheels. the engine braking was basically just pushing backward with the rear wheels, kinda straigntening the truck out in the process.

if i couldn't stop fast enough, shifting into reverse and giving it gas to finally get some traction has worked to keep me from hitting stuff in dire situations

i wouldn't really suggest such things though.
 
First off I am an engineer and I have a degree in physics. I have a good understanding of what makes cars lose traction. I live up at the top of a very steep hill at 7,200 foot elevation that ices up very frequently and is not sanded as much as it should be. I get lots of practice going down that hill to work on cold mornings.

You get finer control using your brakes for braking than using your engine. What I do depends on the hill and the type of car that I am driving (rear wheel drive, front wheel drive, 4 wheel drive, all wheel drive, automatic transmission or manual).

I would never put a manual transmission car in neutral going down an icy hill, but I frequently go down parts of the hill with my foot on the clutch. I might be able to conceive of going down a hill with an automatic transmission in neutral I don't think that I have ever actually done it.

I would never use engine braking to provide more than a slight drag as I go down an icy hill. I normally use engine breaking only in a 4-wheel or all-wheel drive vehicle. When I go down the hill I want to apply the minimum braking to do the job and I want to apply the braking evenly and smoothly to all of the wheels. In a rear wheel drive vehicle your engine breaking usually only works on one of your rear wheels. These are the wheels with the weakest traction when you are slowing down. If you let one of those back wheels lose traction you are in trouble and you don't have a nice symmetrical drive to get you back out. In front wheel drive cars you usually have better balance between your left and right side and you gain a little extra load on these wheels when you brake so you are better off using engine braking than if you had RWD. Engine braking is still only going to work on two wheels so you are twice as likely to break traction if you downshift too low. Recovery is a bit better in a front wheel drive car since a little acceleration can pull you back into line and get the wheel rotation to match your surface speed.

If you only use a little bit of engine braking with a 4WD or AWD vehicle you can relieve some of the burden from your brake pads and transfer it to churning your engine. For the hill that I go down I use 3rd or 4th gear and mostly use my brakes. I start out at the top of the hill going very slowly. I apply my brakes lightly (sort of underbraking) and allow the car to pick up a little more speed as I go down. If I didn't brake at all I could go down the hill ballistically without needing traction except to steer. Since it just wouldn't be safe to let the car get up to 70 on an icy road I compromise. I start at the top of the hill at 10 mph and let it get up to 30 by the time I reach the bottom. That allows me to use less braking force than trying to stick to a fixed speed for the whole trip. Since I am in a relatively high gear all I need to do to regain traction is release the brake (and maybe the clutch if I have manual transmission). The engine will put all the wheels into rotation at a speed that approximates my ground speed and recover traction.

One of the reasons that this approach works is that icy weather helps to keep your brakes from overheating. They start out at around 32F and have cold air to help them shed heat build-up. This helps to preserve braking effectiveness and reduce brake wear (hot brake shoes wear faster than cold brake shoes). Another reason that this approach is good is ABS braking systems. Engine braking does not have microcomputers that kick in to adjust the wheel drag when you lose traction the way that your ABS system does. If you carefully use your brakes going down a hill and one of your wheels loses traction an ABS will release just that wheel to optimally recover traction. You don't get that kind of control with engine braking.

Now I say the above for hills of reasonable length. When I am coming down the I-70 grade from the Colorado ski areas down to Denver there are steep grades that last for more than 10 miles at a time. In that case I do downshift, but only in moderation. I shift down to 4th from 5th or down to 3rd from 4th. I am ready to push the gas if I start to lose traction.

I only own AWD vehicles in this country. Whenever I can I find ways to avoid the icy hills. Sometimes I just stay home.
 
The problem with you southerners is that when it does snow (less than 1") no one knows how to deal with it...We Yankees love it;)

Yeah, right! When did this happen? :D

I was stationed in Connecticut back in 1977-78. I drove from the base to my apartment in Springfield, MA. through a blizzard that paralyzed the entire state of CT for three days. The funny part was, I was driving a Triumph GT-6 with four inches of ground clearance and passing mid-size cars abandoned on the road. I really wondered how a place that gets snow every year could have that many drivers with no clue how to drive in it.

At least we have the excuse of inexperience ;) :D
 
Yeah, right! When did this happen? :D

I was stationed in Connecticut back in 1977-78. I drove from the base to my apartment in Springfield, MA. through a blizzard that paralyzed the entire state of CT for three days. The funny part was, I was driving a Triumph GT-6 with four inches of ground clearance and passing mid-size cars abandoned on the road. I really wondered how a place that gets snow every year could have that many drivers with no clue how to drive in it.

At least we have the excuse of inexperience ;) :D

Don't look at me, I was in Maine in 1977-78 and did just fine:D:D:D
 
The problem with you southerners is that when it does snow (less than 1") no one knows how to deal with it...We Yankees love it;)

We know how to deal with it..........We stay indoors and drink good Scotch.:D
 
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