The Snow Driving Uphill In Reverse Debacle: Myth or Fact?

@B.L.E You are right about the manual and I have driven them all my life, so I just put it in 2nd and good to go. I have never been able to figure the manual shift option in the automatics though. Seems like some have a rev protector that even if you put it in second, it will “protect” the transmission by upshifting at high RPM’s. I might be wrong.
I had a Mazda CX-9 and it was the only automatic that would actually show what gear the transmission was in on the dash. It was neat and I don’t think it is that complicated of an option to have.

I had the options in older cars, d2, but the last 20 yearsI have had awd or 4wd option and have not even had to think about it.

My wife’s Honda Element allows 2nd gear starts, and I believe so do many other Hondas with automatic transmissions.

Problem: Driving car up a hill after a snow storm.

variable A - RWD or FWD
variable B - AWD or 4WD (differential locking gear box)
variable C - snowchains on or off
variable D - Snow is fresh or compacted
variable E - Snow tires on drive wheels
variable F - Manual transmission or automatic

Solution: If FWD go forward, if RWD go backwards

The solution changes where fresh show has more traction (friction) with the tire. This is increased with snow tires.

When snow is compacted to the point of being ice, there is not much friction for any case, except with snow chains.

Physics: Friction is defined in a static form and kinetic form
Static Friction - the two materials are not sliding against eachother (car tire not spinning)
Kinetic Friction - the two materials are sliding against eachother (car tire spinning)

You always have more traction when the tire is not spinning, so it is best to gently press the accelerator and slowly add power, as to not have the tires spin.

This can be assisted by putting the transmission in a higher gear, so the power can be added slower and not go from static friction to kinetic friction. In most automatic transmission cars you can put the gear selector in “2” and this starts the motion of the car in 2nd gear, instead of 1st.

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GRAPH: Imagine driving up the hill and adding power, then the breakaway happens and change from static friction to kinetic friction

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TABLE: In every case listed the Static Friction is always greater

Exactly wrong. Going up hill there is weight transfer to the back axle, so that should be the driven axle.

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I was thinking from the instance of fresh snow, If your drive wheel is in the front it will have greater friction, but if it is in the back the drive axle will be on compacted snow.

Except that tire traction does not work as this theoretical friction model presents. This theoretical friction model uses smooth surfaces to describe the action of friction. Neither tires nor snowy ground is smooth. Tire friction is a function of embeddability and surface roughness as much as friction coefficient. That is why tires can generate more tractive force than the force of weight placed upon them. I.e. “G” forces greater than 1.0.

Snow tires are designed to capture and trap snow in their treads to provide traction in deep snow. The snow in the treads has a higher level of grip to the snow of the road than the rubber itself. The rubber is also much different to give it an affinity for snow, ice and slush.

Often spinning the tires in semi-packed snow can fill the treads and provide better grip that stationary tires. That is the opposite of the theoretical physics model. Similarly, a locked tire in deep snow stops shorter than a tire kept rotating with ABS.

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I am trying to think of when I might need to know the coefficient of wood on wood . :thinking:

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Yeah I’ve been taking some refresher courses like Western Civ to refresh my memory during the great confinement, and was considering physics or organic chemistry. Based on my eyes glazing over at the above, I think I’ll just skip it. Glad some like it, but I’ll just rely on observation like the Greeks.

Now the reality is, trying to drive a FWD with or W/O traction control up a snowy hill takes some doing. If the traction control goes off, and you continue to give it throttle, you’ll drive the car right into the curb or the ditch. Forget backing it up in a snow storm in anything newer that ten years old because you can’t see where you are backing at the speed you would have to back. So forget about it.

You have a shot at getting up the hill with an AWD though since the rear wheels will kick in when the front wheels begin to spin, so you won’t get driven off the side of the road. Agree with the whole compressed snow idea.

Like I said last week put 100 miles in a snow storm and saw at least 7 cars in the ditch in my travels. Little did I know that the Highway Patrol reported that usually people receive a ticket if they go in the ditch. The ticket is for lack of driving with due care. No idea what the fine is but adding insult to injury, but they claim if you go in the ditch you are either not paying attention, are driving too fast, have poor tires, etc. so fine thee we will. Kinda like getting a ticket if you run out of gas. No excuse they say. So if you are out there experimenting going backward or forward and go in the ditch, try and get out of there before the Minnesota Patrol comes along anyway.

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About 15 years ago, a friend encountered a deer shortly after leaving my house. His old Honda didn’t have ABS, and when he locked his brakes, he wound-up in a ditch. He called me and I arrived at the accident scene before any cops arrived.

A few minutes later one of the very few Black NJ State Troopers came on the scene, inquired about injuries (luckily, my friend wasn’t injured), and he set up perimeter flares. He was the very image of both professionalism and courtesy.

A few minutes later, one of the local cops showed-up, so the State Trooper departed. The local yokel cop was threatening to ticket my Asian friend for reckless driving because he was in a ditch, but because he had managed to avoid killing a deer, there was no evidence that he had tried to avoid a deer collision.

I intervened, and I was able to convince the local cop that my totally-sober friend (with a spotless driving record) had not intentionally driven his car into a ditch.

Anyone who claims that much of the enforcement of traffic statutes is not totally arbitrary, and is not sometime driven by racial prejudice, is not looking at reality as it really exists.

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I’ve been stopped and sometimes ticketed or not by both male and female and haven’t really noticed the difference. I was also stopped by a black local and just warned to come to a complete stop at a stop sign. He was very professional. The same guy responded when my car was backed into in the drive through lane. He was so professional and the report he filed was so well done I provided a good conduct report for his file. The two biggest jerks I encountered were young white guys but both local in their towns. I won’t go into the local jerks from about 1980 investigating the theft of sand box sand since they are long gone. I think a lot depends on the Police Chief or the Commander hiring and setting the expectations. Ours are very good but that has not always been the case.

Man the more I think about it, the more encounters I remember. I’ll probably have to write them down. Gotta say 90% were OK.

Try this experiment the next time you are driving down the highway. Look at the cars going the other way and try to identify the race, nationality, and sex of the drivers in them. Mostly you see the reflection of the sky in the windshield. I used to think that the cops were out to get me because I was a young rebel dude. So I thought I would trick them by driving like a grownup. To my surprise, it worked.
Please actually try this experiment before you respond to this post.

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Most of the questionable encounters with LEOs do not happen at highway speeds.
They happen in places like secondary roads with a speed limit dropping drastically when they go into a small town, city streets, or other low speed locations.
Besides that, if you and the car on the other side are going 60 mph, you’re passing them at 120 mph.

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+1
Additionally, my post regarding the very obvious bias against my Asian friend mentioned that he was already at the side of the road, after going into that ditch, and was thus fully visible to the cop. The local yokel cop’s attitude/demeanor was totally inappropriate and–IMHO–was the result of racial prejudice.

Threatening the victim of an accident–in an area that is infested with deer–with a ticket, based on a presumption rather than on anything that the cop had observed is just… wrong.

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