Model S Slid Away...

[MikeHolliday]

I have had 5 different ICE car slide down the drive in winter the exact same way... I suggest that a number of people here should go back to school and take a few Physics classes. It is simply a coefficient of friction, at the point where friction becomes low enough the car will slide... There is nothing wrong with the car.

 

[dmurphy]

I have had 5 different ICE car slide down the drive in winter the exact same way... I suggest that a number of people here should go back to school and take a few Physics classes. It is simply a coefficient of friction, at the point where friction becomes low enough the car will slide... There is nothing wrong with the car.

Exactly. I found our Enclave in the middle of our street once. Was glad it didn’t bounce off the opposite curb.

Now, whenever there’s snow or ice in the forecast, I play Junior Ramp Agent and chock the wheels. Problem solved.

 

[Handlebars]

I believe that you can solve this problem with oil dry (auto parts store, 40 lb. bag). When you park the car, remove the snow behind each wheel on the downhill side the width of the tire about a foot long. Add oil dry about 1/2 inch thick for about one foot long, the let the car roll back on it and park.

I carry two cans (holiday popcorn cans) in the frunk when traveling in winter, and keep it in the garage if needed for ice on the driveway. We don’t have much snow in Georgia, but it is nice to have if needed. It also is good for drying up water spills from hot water heater’s, frozen pipes, etc.

Good luck,

Handlebars

 

[erniejenson]

I spent a good part of my life living in ND. Many secondary roads in ND are not plowed, no sand or salt, and one get a skill for driving quickly on ice and learns what is dangerous. When the ice is very cold, traction is good. When the temp is close to melting or melting the traction is much less. If your tires are warm from driving and the sun has warmed the dry pavement and you pull onto a icy drive with a slope there is a risk. The tires are hotter than a melting temp and the surface on the ice gets wet from melting from the heat of the tires. When the car starts sliding it will keep going. This is not unique for a Tesla. Unfortunately, just physics at work!

 

[TSLA Pilot]

Automatic transmission ICE cars have a parking pawl (gear) that engages when in park, keeping the engine and transmission from rotating. From what I’ve read, there is no such feature in Tesla drive units. They could hold the motor stationary with an applied field, but that would consume energy. Don’t know…. It’s not a clear parallel…

This has NOTHING to do with why the car slid down the hill.

ANY car, parked on a slippery hill, may slide once the driver exits. The regular brakes works on all four wheels; the parking brake works on just the rear, on about 99%+ of cars. (The exception is some older Subarus, from the 80's.)

The wheels did not rotate, the parking brake had them locked. This is pure and simple physics.

 

[David.85D]

This has NOTHING to do with why the car slid down the hill.

ANY car, parked on a slippery hill, may slide once the driver exits. The regular brakes works on all four wheels; the parking brake works on just the rear, on about 99%+ of cars. (The exception is some older Subarus, from the 80's.)

The wheels did not rotate, the parking brake had them locked. This is pure and simple physics.

I don’t disagree with you, but what I wrote is still true. And, for whatever reason, my Tesla is the only car that has slid on my driveway. We’ve owned Bmw, mini, Subaru and a Toyota here.

I don’t think it is Tesla specific. perhaps it’s the low rolling resistance tires or the low friction bearings on the non- locked wheels?

 

[domodan]

I don’t disagree with you, but what I wrote is still true. And, for whatever reason, my Tesla is the only car that has slid on my driveway. We’ve owned Bmw, mini, Subaru and a Toyota here.

I don’t think it is Tesla specific. perhaps it’s the low rolling resistance tires or the low friction bearings on the non- locked wheels?

It’s probably largely due to the fact that it’s undoubtedly 40% (or more) heavier than all those other cars. Has nothing to do with the low friction bearings or non-locked wheels, because the wheels stayed locked.

 

[TSLA Pilot]

I don’t disagree with you, but what I wrote is still true. And, for whatever reason, my Tesla is the only car that has slid on my driveway. We’ve owned Bmw, mini, Subaru and a Toyota here.

I don’t think it is Tesla specific. perhaps it’s the low rolling resistance tires or the low friction bearings on the non- locked wheels?

And also consider: climate change and the mass of a Tesla perhaps?

Snow/ice at just below freezing temperature will state change to a liquid under pressure. Tesla tire pressures tend to be higher (since the cars weigh so much), and winter temps are likely higher than in past years, all adding up to more sliding Teslas when parked on snow and ice.

Sounds like a good theory anyway . . . .

 

[David.85D]

Go back and look at the curves R1 R2 and R3 in post 37 - those are the friction curves for three different tire compounds. The paper presented that data in a de-identified way so we can't draw any conclusion about the differences (such as snow vs LRR vs Regular), but the behavior at low temps is highly dependent on the tire compound, contact pressure (weight of vehicle divided by contact area of the tires - not tire pressure, but they are related), and ambient temp.